Project Schedule Delays – Causes, How to Prevent and Mitigate

18 min. read

“If you are in the project delivery space, the project schedule delays are inevitable.” Do you agree with this statement? Many project managers think that completing projects on time appears only in books. Well, this is not true. With project management office practices, proper project management skills, proactive risk management, and effective planning, project schedule delays can be minimized even if they cannot be lowered to zero.

We will be going over the following in this post:

  • What is a project delay?
  • The common causes for schedule delays in projects
  • How to mitigate project schedule delays

Let’s go through each of them one by one.

What is Project Delay?

Before diving into the details of schedule delays in projects, let’s describe what the project delay is. There is a magic triangle that is very popular in project management. There are three fundamental aspects or boundaries of each project. These are the cost, scope, and schedule.

  • The scope defines what will be delivered throughout the project and the end results of the project.
  • There is a defined budget to complete the project that is planned to be spent throughout the project. You can read more about project cost overruns.
  • The project team works on the project scope and spends the project budget to complete the project on time. The schedule of a project defines the planned dates to complete project activities and the overall project.

Project Schedule Delays

If the planned project activities cannot be completed on time, this is called a “delay”. Note that delays can be on the activity level, phase level, or overall project level. For instance, if one of the project team members is completing an activity in eight days while the planned duration was five days, this is an activity level schedule delay. There can be several phases of a project. If any phase is exceeding the planned deadline, this will be considered a phase delay. Finally, if the overall project deadline is delayed, this will be considered a project schedule delay. Project overruns can be a project as well as non-project-related.

Causes for Project Schedule Delays

When we surveyed 425 participants who attended our corporate training programs, 47.2% of the respondents reported that schedule delays are the top project management issue in their organization.

Project-Management-Issues-in-Organizations-1024x527 Project Cost Overruns - Reasons, How to Prevent and Manage

As you can see from the pie chart, the majority of the project managers reported that schedule delays were the number one issue in their organization. There can be several reasons for a project delay. We will be going over the top five reasons for the project schedule delays.

Causes for Project Schedule Delays #1- Ineffective Scope Management

The project team must gather detailed customer requirements and make the scope as clear as possible. If the scope is not clear, there will be misunderstandings between the customer and the project team. And this will result in rework and project schedule delays.

How can an unclear scope cause a delay? Let’s explain it a little further. For instance, a customer did not clearly communicate their needs to the project team. The result of this will be an ambiguous definition of the scope statement. When the team starts with product development, some of the work might be done based on assumptions. Furthermore, the team might even feel the need to improve the features, or even add more features to make the product function or look better. Hence, there could be scope creep and/or gold plating happening also.

It is possible that the customer has communicated clear requirements. However, the project team did not make an effort to write the requirements well and in detail. Consequently, the scope statement might describe more product features than requested by the customer. There is also a chance that some product features weren’t written clearly or in detail. What would happen next is that upon inspection of the deliverables, the customer would find out about the issues. They would see a mismatch between what they wanted and what was delivered. So, they may request rework on some of the deliverables, causing project schedule delays.

As you see, ineffective scope management could easily become the reason for the project delay. Hence, the PMs and their team must ensure that they gather maximum information from the customer and document it well. The project manager then must make sure to deliver customer requirements as expected. They should understand that unclear scope could decrease or increase the amount of work that needs to be done. So, they should not let project schedule delays occur due to ineffective scope management.

Master of Project Academy offers virtual, in-person, and online training courses in PMP (Project Management Professional), CAPM (Certified Associate in Project Management), and Core PM classes where our experienced instructors explain with real-life examples how to collect requirements, develop clear scope statement, manage and control the project scope. By attending our award-winning courses, your employees will get practical guidelines on how to prevent scope creep and how to deliver project scope and requirements as per the customers’ expectations.

Causes for Project Schedule Delays #2 – Unrealistic Activity Estimation

Once you have defined the project scope, now you can define and estimate the project activities. Since the estimation of every single activity can affect the project deadline, you must ensure definitive and realistic activity estimation. If you make unrealistic activity estimations, you will surely witness project schedule delays.

An activity could be done in 10 days, for instance. However, if you deliver it in 20 days, what would be its effect on the project? Well, it will cause the project to finish 10 days later. Imagine then if estimation for several activities isn’t done correctly, how much impact this will have on the project deadline?

In order to estimate activity duration, the scope must be clear. If the scope was not clear but you are an expert in estimation, your estimations will not help a lot. It’s because when the activity starts, you may have to make scope adjustments. And this may cause some activities to deviate from their plan. Furthermore, the project manager should know how competent their resources are and how productive they are to complete the activities. The PM should also know about the availability of the material and equipment required to complete the activity. Based on all this information, they can then correctly estimate project activities. Furthermore, the project manager should use their expert judgment to estimate the activity and not make assumptions.

The best estimation is often based on past experience doing a similar activity. However, when you have not done a similar activity before, you could apply various estimation techniques for activity estimation. There are many estimation techniques that can be used, and some are also explained in the PMBOK guide. These include Analogous estimation, Parametric estimation, and Three-point estimation. These estimation techniques save you from having assumption-based estimations and rather having a realistic activity estimation.

By attending a PMP, CAPM, or Core PM training course, the participants will receive an in-depth understanding of how to estimate activity durations using various estimation techniques. Furthermore, the participants will improve their skills in planning, managing, and controlling project schedules. Our instructors will provide you with practical examples of how to recognize triggers that might cause schedule delays, how to manage and mitigate schedule-related issues, and apply successful tools to bring project schedules back on track.

Causes for Project Schedule Delays #3 – Improper Risk Management

Every project has a certain level of risk. In fact, every individual project activity may have some level of risk associated with it. If a risk occurs and there is no ready plan to deal with it, you will experience project schedule delays. Depending on the severity of the risk, the delay could be minor, but it could also be quite significant.

However, when you have proper risk management in place, you would analyze the risks in more depth. You will look at every possible issue or scenario that could cause a delay in the project. You will also ensure that proper risk assessment is done, risk owners are assigned, and the risk control plan exists and is also implemented well.

Once you have identified the risks, you should now properly assess their probability and impact. If you’ve determined the risk but didn’t understand well the severity of its impact, its planning won’t be worth it. So, it is important to know how vulnerable your project, software, and financial assets are to the risks. You should also know what are the chances that the risks will occur and cause any damage. Furthermore, you should also categorize and prioritize the risks to help you focus and manage them well.

Use reserve management to handle project schedule delays

One of the risk management strategies to overcome project schedule delays is reserve management. However, often due to the absence of reserve management project schedule delays occur. If you know that risk could occur and you’re sure that it’ll cause a project delay, you must add a contingency reserve in the project activities. Since the contingency reserve is a pre-approved amount of time you can use to manage schedule delays, you can use it anytime without seeking permission. Delaying the activity, if necessary, within the reserve time won’t be the wrong thing to do at all. If you want, you can also add the reserve in project phases, or as a whole, in the entire project. So, when a risk occurs, you will utilize the pre-planned reserve to save the project from going past the deadline.

So, in the absence of risk management, risks will occur, and you will not be able to handle them well. Therefore, proper and continuous risk management is very important if you want to avoid project schedule delays. It will help you not only in meeting project deadlines but also in fulfilling the project budget.

Master of Project Academy offers PMP, CAPM, and Core PM training courses where participants can receive a solid understanding of how to identify, and properly manage project risks and assign realistic contingency reserves. Through a number of clear and practical real-life examples, our instructors will make sure you are confident applying risk management strategies to your projects.

Causes for Project Schedule Delays #4 – Resources

Assigning competent resources to the project activities is crucial. If you assigned a junior team member to an activity that requires seniority, what would happen? It is obvious that the activity will take longer to complete. This will then result in project schedule delays.

Assigning an inexperienced resource may be good in terms of saving money. However, your project activities may end up delayed just because of the lack of proper skills needed from that resource. . A resource who is inexperienced to do a particular job may be slower than expected in completing the activity. Or probably they do not have enough skills to produce the deliverables as expected, causing a project rework.

We know that a project often consists of hundreds or thousands of activities. You can imagine then how much collective delay inexperienced or resources who do not have adequate skills could cause to these activities. Competent resources on the other hand have many advantages. They are not only good for completing the activities, but they can also focus on delivering the project objectives. They also aim to work faster, reduce waste, and incorporate their creativity to achieve the best results.

Therefore, the project manager should carefully assess the technical and non-technical requirements of the project activities. Make sure to assign competent resources to get the job done. The Project Manager Officer leading the PMO of an organization must facilitate collaboration, knowledge sharing, and a servant leadership environment to maximize project management efficiency in the organization.

  • Learn more about Master of Project Academy’s Leadership Program where your leaders will get instructive and hands-on training through interactive exercises, case studies, templates, and techniques that can be customized to your organization’s specific needs.

Causes for Project Schedule Delays #5 – Gold Plating

Gold plating is a project management term. It is defined as “doing more work than what is required”. In some cases, project resources continue to add new functions or features, or they try to do more although their particular task has been completed. This causes project schedule delays. Project management is all about delivering a defined scope, within a defined budget and schedule. It is very important to remember that the project team should not be delivering more than the agreed scope.

Gold Plating may be good for the customer as they would be getting additional features for free. However, it would cost the project more money. In some cases, the customer does not like to get additional features. So, they may not be happy with the extra effort that your project team has put in.

The project team gold plates with good intentions, which are obviously to please the customer. Sometimes, the project manager adds extra features to earn credit. Or, they may want it done to divert customers’ attention from defects or to prove their team’s ability. However, it may backfire. In either case, whether the customer likes gold-plated outcomes or not, you will face project schedule delays. Not just this, you will incur more costs on the project as well.

How to Mitigate Project Schedule Delays?

There are 5 fundamental ways to mitigate project schedule delays and we explain them in detail below.

1-) Make Project Scope Clear

If the scope isn’t clear, there may be a mismatch between what you’ve delivered and what the customer wanted. If there are mismatches, the rework activities will cause project schedule delays. So, for the scope to be clear, we should, first of all, make sure to collect the customer’s requirements thoroughly.

When interacting with the customer, you must make sure to ask as many questions as possible. Try to get maximum information until the customer confirms that you have understood exactly what they want. Do not make any assumptions and rely on them! The next step is to define a clear project scope. The scope includes the acceptance criteria, constraints, exclusions, and the detail of the deliverables needed. It also includes a description of the work needed to produce the required deliverables. Hence, defining a perfect scope, which is also clear, unambiguous, and complete is very important. It not only helps stay on schedule, but it also helps you run the project smoothly.

2-) Acquire Competent Resources

Competent resources will make realistic estimations and complete the activities as much on time as possible. Competent resources will focus on project goals and make sure they are working towards the goal. They will be more productive and more resilient to stressful situations. They will demonstrate creativity and resolve problems quickly. Furthermore, with basic project management knowledge that they may possess, they would have the ability to work through the plans.

Hence, having competent resources will help in completing the project work as planned and also preventing difficulties along the way. Thus, the project manager must know the level of competency required in the project activities and acquire the resources accordingly. Competent resources will prove to be very helpful in meeting the project deadlines and preventing project schedule delays.

3-) Effective Change Management

Effective change management is necessary to ensure a consistent, measurable, and structured environment to deal with the change requests. Your organization should have a document that defines the procedures and the workflow for effective change management. And, the PM should ensure that every change request should go through proper change management.

After you have finalized the scope, you must manage every new requirement through change management. During project execution, there is often a need to make changes. Anyone may request changes such as project resources, the project manager, the sponsor, or the customer itself. The project manager, along with other key stakeholders, should assess the change requests. They should evaluate the effect of the changes and understand what is the impact if these changes do not happen. Any change that you do not properly assess and the one that is not beneficial must not be authorized and implemented. If you authorize such a change, its implementation will unnecessarily consume project time and cause project schedule delays.

Once the project manager has assessed the change request, they must inform the sponsor and the customer. They should inform them how the change will affect the project budget and the schedule. Also, they must take the sponsor’s and the customer’s approval before allowing their team to work on the change. If effective change management is not in place, the project may face many problems in its completion. And there could be many schedule delays.

4-) Accommodate Risks’ Schedule Effect

When a risk occurs in a project, immediately we can notice two effects on the project. The project will require an additional budget and time to overcome the effect of that risk. Therefore, risk management must ensure that schedule buffers exist for the probable risks that can affect the project schedule.

During the project planning phase, the PM should determine the right amount of buffers to include in the project schedule. The buffers required should be based on a thorough risk assessment and not on assumptions. And, during the execution phase, if a risk does occur and causes an activity delay, only the buffer should be utilized. Time consumed outside the buffer will delay the project, hence doing this must be avoided.

5-) Take Schedule Baselines and Do Periodic Baseline Assessments

Once you have developed the project schedule baselines, these will help in comparing the actual progress with the planned schedule. To know whether you are going ahead or behind the schedule, look at the schedule baseline. Also, look at the actual progress information.

When comparing the schedule baseline with the actual project progress, if you find a delay, you should take action. And, if the project has already consumed buffers, then you must act immediately. You should do something to not let the project be delayed further and bring the project back on track. Therefore, it’s important for the project manager to be knowledgeable of various project management techniques to fix the project delay.

For example, when there is a delay, the PM could add more resources to complete the remaining work. Or make the existing resources work overtime to finish the task earlier. Or, they may reduce any lag between the activities or make them start doing the work activities in parallel. They could even work during weekends to add extra days to the project. By reducing the duration of some of the activities, they can also compress the schedule. What if you have looked at all these options and still couldn’t compress the schedule enough? In that case, you may need to remove some activities from the project. You may identify some activities that can be safely removed, and the project can still function well without them.

When the project schedule is delayed, the PM should determine the best option to mitigate the effect of the delay. It is possible during baseline assessment you determine that currently there is no suitable option to eliminate the project delay. In this case, you may request the management to allow the use of the management reserve. But this should be your last resort to fix the project schedule delays.

Summary: Project schedule delays

Project schedule delays have a very negative effect on clients, consultants, and contractors. They lose trust in you. And they do not look at you with confidence in terms of future relationships and business growth. Not just this, even the project resources may lose their morale. When they see the project is in trouble, they think that putting full effort into it wouldn’t be worth it. Since the project will fail in terms of schedule anyway, they don’t give much attention to it.

PMI Pulse of the Profession conducted a survey in 2018. According to the survey, just 52% of the projects worldwide could be completed on time. This is a shocking figure indeed. But it is the bitter truth that most of the projects face delays. Whether it is an IT project, Civil, Mechanical, or any other project, schedule delays will be there.

One delayed project may be acceptable but when several projects start to be delayed, there will be unacceptable or irreversible consequences. So, it is ultimately the responsibility of the project manager to try to avoid project schedule delays. Or if they can’t be avoided, at least the effects should be mitigated. And for the PM to do so, they should have effective reserve management. Moreover, they should have competent resources for the project. Their activity estimation should be correct and there must also be effective risk management in place.

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