Project Resource Estimates

Project Resource Estimating – How do you get accurate estimates from your resources?

Wow, this is such an important topic and one that project managers deal with a lot, especially nowadays when their team members are working on so many projects at once and spread very thin.

Hi everyone, Bill Dow here, and I wanted to cover in this article is the challenges of getting accurate estimates from your project resources. I have to say as a Project Manager who has been managing projects for a long time, resource estimation is one of the hardest jobs for any project manager. Hopefully, you can pick up some tips and tricks to make your life a bit easier.

The project resources are struggling to provide high-quality estimates because they are spread so thin and working on so many projects. Add the complexity of working remotely, working on multiple projects, and project managers will struggle to get accurate estimates from their team members. Before we go to far, I have an YouTube video on this same topic I would love for your to check out.

Click the link and let me know what out think! 

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Why is it so hard to get accurate estimates?

I believe in my 30 years of doing this project management work, and being a project manager, the biggest and most important reason team members struggle to give good estimates is context switching. Context switching from one project to another is something that is happening more and more each day and when team members are asked to give an estimate, they do not know how to judge how long context switching will take them between projects.

Therefore, when team members are giving an estimate for a project task, with them also dealing with multiple project assignments, they are going to struggle to truly be accurate on how long something will take. I don’t blame them. It happens, and I see it all the time. As long as we keep project team members working on multiple projects at a time, this is just something we will face in this industry.

Second, project resources are working on so many projects today that they don’t have the time to accurately estimate their next project’s tasks. In most cases, they end up just doing their best guess on these estimates, not really knowing if it is accurate or not. I can’t stress enough why this is so important to understand. When we have so many people assigned to so many projects at the same it time, is almost impossible to provide proper project estimates.

Resource Estimating

With the release of Agile, when it was first introduced, we saw project teams that were dedicated to one project and only one project. When those project team members were asked to provide estimates, they did so using Agile estimating methods such as t-shirt sizing, poker planning, or the Fibonacci Sequence and after a couple of sprints, they were pretty close in their estimates.

Well, not all companies have embraced Agile in that manner and so more projects are Hybrid these days, which means team members are not working on single projects and therefore have to spread their time between projects. If we see project team members get stuck on a task on a project that they never expected, or something occurred on another project that was unplanned, it could again throw their project’s estimates off.

This is the risk you take when we keep assigning people to multiple projects and those projects run later than expected. Have you seen that before? I have, I see it all the time.

The third reason and this happens a lot at some companies more than others, but that is when we have resource managers providing estimates on behalf of their project resources. So a Development Manager, for example, would provide an estimate for a developer. When someone is estimating on behalf of another person, what are the chances of those estimates being off?

Of course it will happen, because people have different experiences and skill sets, and a manager may think it takes three days when a resource knows it will take five. This often happens when the resource doing the work has time to look at what is being asked of them, and they can assess what they have to do compared to if they know how to do it or not. This self-reflection a person does once they see the task there are assigned can certainly be off from what their manager suggested, because they are closer to what they can and cannot do.

Ok, now we know the why, how can we help these resources provide more accurate estimates?

Here are some of my suggestions. I am interested in knowing what you do on your projects? I am also interested in know what resource management tools you use in your PMO or for your projects? Is there particular project management software you use to help you with resource management? If you have specific resource management software that you use, I would be interested to know that as well, I have not seen a lot of great tools in this space.

Let the resources provide the time estimates they are most comfortable in providing for their tasks. Remember, they are one’s doing the work, so they should provide the estimates. We often call these historical estimates or expert judgement and it is where the project resources say, “I done these kinds of things before I think it will be a week, or two weeks…etc.” You let them provide their expertise opinion of the task and then, as project manager, you tweak and adjust as they get working on the effort.

1. PERT Estimating – I love this estimating model and it is where you get three values, Optimistic, Pessimistic and Most likely for a project task. When you have these three points of estimates for a project task, I believe your estimates are so much more accurate than historical estimates. The PERT Estimation technique is one of my favorites and one that I don’t believe is used enough on our projects. The great thing about PERT estimating is the calculation is so easy, project managers should just allow the software to calculate the PERT Estimates.

2. In Agile projects, as noted above for estimating, I like T-shirt sizing the users stories. One of the most popular methods is the Fibonacci sequence, but there is a variety of ways to do it. Pick the one that works for your company.

3. Other popular techniques include analogous estimation, parametric estimation, and bottom-up estimation. Spend the time and learn each of these models. Now we know the different methods, let’s look at how to create these estimates in more detail. Whatever, the technique you use, all of these processes are key tools to help project managers in this resource estimating process.

How does a project resource actually provide the estimate?

Let’s look at that step-by-step process as well. If you are new to project task estimating this is a series of steps I have used before and wanted to share:

1. Break down project tasks: Start by breaking down the project into smaller, more manageable tasks. I like to see tasks broken down no bigger than 2X the reporting period for the project. For example, if you report project status every week, I shoot for project tasks no larger than 10 days in my project plans. Smaller tasks are easier to estimate accurately since they involve fewer variables and dependencies and when you do this each week, you can use the 0, 50, 100 method.

Have you started working on it (50) or completed it (100)? When you use the reporting period for the duration of your tasks method, you have a much better handle on your project task estimates and if your team member is going to make their commitments.

2. Clearly define the scope: Make sure that all project stakeholders clearly understand the project’s scope for a particular task. There is nothing worse than being unclear or vague and expecting a team member to provide an estimate with a lack of information. Of course, this is going to lead to inaccurate estimates, which will be no fault of the project team members. Get your scope locked down and you will reduce the chance of the task estimates being off. If that project resource worked on a previous project that was much like this one being proposed, it would help for sure with the estimation process.

3. Involve relevant team members: Include team members who will perform the tasks in the estimation process. They have the best understanding of what is involved in completing specific activities and can provide valuable insights into this process.

4. Leverage expertise: Talk to subject-matter experts or experienced team members who have successfully completed similar tasks before. They may bring valuable insights and recommendations about challenges or time required to complete a particular task, which would be a leading indicator of how long something will take to complete. This is where people who have worked on a past project would be very valuable in this process.

5. Provide simple & clear instructions: When requesting estimates from your team members, provide them with simple instructions on what information is expected for the task. This will include assumptions made, potential risks identified, dependencies considered, and any other relevant details. The clearer you can be on the instructions, the more accurate your team member will be when providing the estimates.

6. Allow for buffer times: Encourage your team members to include buffer times when providing estimates, especially if they are on multiple projects. The more projects they are on, they may need more buffer time, so factor that in when possible. There are unexpected issues, resource unavailability, or learning curves that may cause delays during project execution. This can be easily overlooked when first providing the initial estimates, so make sure they are accounted for when possible. It is best practice for the project manager to add this buffer to the project plan where possible.

7. Review and validate estimates: Once you receive estimated durations from your team members, review and validate them. Then, as the project work begins, closely track those estimates to actuals and then course correct where needed. Sometimes project tasks will come in over and sometimes under, hence why we call them estimates, and as the team does this more often, they will get better at completing them. Make sure the project plan is updated and as accurate as possible with these new validate estimates.

One of the key components of this whole process is that the project manager must determine the accuracy of the project estimates provided by the resources and ensure they look and feel right. You can’t just blindly take the estimates, they need to be vetted, tested and challenged in some cases. Good project management means having those conversations with the team members and having the difficult conversations if it comes to that. It is these kinds of conversations that can only improve the accuracy of the project in the long run.

Final Thoughts

As noted above, resource estimating and getting accurate estimates from your resources is very difficult these days. So many resources are spread so thin on time and working on so many projects for them to accurately provide estimates is hard. But, push through it, follow the techniques I outlined above and keep driving the team the best you can.

What do you think?

If you like this article, you will like this next one on the Project Management Playbook. It is located here: Project Management Playbook article and the cool news it it comes with a free ebook. Check it out. Or you can check this one on Project Management Techniques as well, it is one of my popular ones so would love for you to check out.

Bill Dow, PMP

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1 thought on “Project Management Resource Estimation – How do you get accurate estimates from your resources?”

  1. This article really delves into the nitty-gritty of resource estimation in project management. I appreciate the practical tips provided, especially the emphasis on communication and collaboration. It’s so crucial for accurate estimates!

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