Project Management

Six Mistakes to Avoid When Making Your Project Schedule

Published by and in Project Management

Update 08/03/2017: We’ve added more recent research and statistics, and updated old links.

You’ve heard the statistics before: projects fail, and often drastically. For example, fewer than a third of all projects are successfully completed on time and on budget, and 75% of IT executives believe their projects are “doomed from the start.”

What if I told you that there are of six mistakes that project managers make that directly correlate with these project failures? And what if I told you that all of these mistakes are entirely avoidable? And that all of them stem from project planning?

The 6 pitfalls to avoid in project schedules

Project planning and scheduling are integral to the success of a project. Whether you’re using Gantt charts, the critical path method, or planning out your sprints, these project management mistakes will be a death sentence for your project.

Avoid them at all cost.

Mistake #1: Not defining your project’s purpose

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The Project Management Institute notes that ineffective communication leads to project failure one-third of the time. While project managers should have a clear communication plan in place while the project is ongoing, the first step in the entire project itself should be establishing the project’s purpose and goals, and communicating those to the team.

Managing Projects writes,

“Don’t be fooled! Before a team develops a schedule, members must have established an understanding of the project’s purpose, agreed on goals, selected the best course of action for achieving the goals, created a comprehensive work breakdown structure, and assessed project uncertainties.”

Make sure that you communicate with your team why the project is important, how it will help the company, and what the goals are before even starting the scheduling process.

Mistake #2: Not establishing requirements

While the vision for your project may be dead on, it’s important to finalize what requirements should be included in your planning process.

Many, including Duncan Haughey from ProjectSmart, believe that project managers should get a written statement of requirements from the customer.

He writes, “This document is a guide to the requirements of the project. Once you create your statement of requirements, ensure the customer and other stakeholders sign-up to it and understand that this is what you have agreed to deliver.”

Doing so pushes scope-change risks onto the customer and off your team.

Of course, if your team is Agile, you may struggle with establishing requirements early on. But with that said, having a starter list will provide a broad outline for your project as it progresses, giving structure to scope and project planning.

Mistake #3: Getting your estimates from nowhere

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If you aren’t communicating with your team about their ability to meet deadline, or if you’re being overly optimistic with your estimates, you’re going to have a hard time meeting deadline no matter what.

Make sure to meet with your team to understand their capacity to take on your project, and understand how each team member or team lead expects themselves to perform. Use project management software to produce reports of past productivity, and use those measurements to calculate what your team is capable of in the future.

Mistake #4: Giving inexact estimates because of stakeholder pressures

We’ve all been there—you know you can’t get a report done by Thursday, but you promise it anyway because of managerial pressure. And by the end of Thursday, everyone is rushed, stressed, sloppy, and ultimately disappointed. You want to avoid this mistake at all costs.

There is a fine line between setting high expectations and generating unrealistic goals for your team. Do what you can to meet your stakeholder’s requirements, but take the time to evaluate risks associated with pushing deadline so hard. If it simply cannot be done, all stakeholders involved, including and especially your team, will appreciate your candor. Pick your battles, but use honesty every time when evaluating what can and cannot be done.

Mistake #5: Forgoing risk management

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Info-Tech Research Group found that organizations with a formal risk management strategy are more than half (53%) as likely to have “management success” than those with a reactive approach. In other words, establishing and maintaining a risk management strategy from the get go is crucial to a project’s success.

Formulating a risk management strategy isn’t difficult, but it is time consuming. As you look through your project schedule, make sure that you have defended against common risks, such as unrealistic schedules, scope changes, and gold plating. Evaluate how pressing each risk is and how big an impact it would make on your project. Then, create contingency plans to offset and respond to a negative event.

For more information on how to plan for risks, check out our “Unconventional Guide to Project Risk Management.”

Mistake #6: Being rigid

Maybe you’re a Scrum guru and refuse to set eyes on a Gantt chart, or maybe you don’t want to hear any more excuses for why a project can’t be delivered. Either way, being inflexible—whether it’s to a specific methodology or to hearing feedback you’re not partial to, is an undesirable personality trait in far too many project managers.

When you make your project schedule, know which project management method you anticipate using and what your requirements are. But allow space, if you can, for some off-the-books improvisation. Few projects go exactly as planned—give yourself and your team the flexibility to adapt to unforeseen problems or unconventional project approaches if needed.

What are other potential mistakes in project schedules

Planning a project takes quite a bit of effort—but taking the time to do it right will increase your project’s chances of success. What planning and scheduling must do’s did I miss? Leave your thoughts in the comments below!

You might also enjoy these other articles about project management mistakes:

3 Mistakes All Project Managers Make With Their Stakeholders

Don’t Make These 5 Mistakes When Buying Project Management Software

5 Dysfunctions of a Team and the PM Disasters They Caused

5 Project Management Failures That Doomed The Human Race In Alien: Covenant

Images by Abby Kahler

Looking for Project Management software? Check out Capterra's list of the best Project Management software solutions.

About the Authors

Rachel Burger

Rachel Burger

Rachel is a former Capterra analyst who covered project management.

Andrew Conrad

Andrew Conrad

Andrew Conrad is a senior content writer at Capterra, covering business intelligence, retail, and construction, among other markets. As a seven-time award winner in the Maryland, Delaware, D.C. and Suburban Newspapers of America editorial contests, Andrew’s work has been featured in the Baltimore Sun and PSFK. He lives in Austin with his wife, son, and their rescue dog, Piper.


Comment by Mary Borysova on

Great article! Thank you for that! And as for me one of the biggest mistakes project managers do is not setting right goals and objectives. And here it’s important to take into account all 4 areas such as money, time, scope, quality. Only then your objective is determined in a complex way. This advice is described in this Project objective guide ( Hope, it will be helpful for somebody!

Comment by Justine Traynor on

All valid tips and to expand on #4: don’t set your target delivery date without doing some level of project planning. Take the time to scope your project and think about the work required to deliver the product. That target date may be unrealistic and you need to set expectations early re: scope, schedule and quality.

Comment by Robby Cutiva on

Great guide for project planning for success. Important focus in risk, schedulling, efective communication, requierements and stakeholders expectations.


Comment by Sanket Pai on

These are all genuine mistakes that project managers make from time to time. According to PMI’s Pulse 2014, organizations are losing an average of US$109 million for every US$1 billion spent on projects. Thats huge!!
Here’s another thing I have learned from my experiences: “Defining wrong success metrics” Your Schedule metrics cannot simply be just around time and budget. You need to define and factor in measurements for resource utilization, resource capacity, time tracking, time on unplanned activities to name a few.
Also on your # 4, I mantra I have learned from my mentor and commit to using it in all my projects “Under promise and over deliver”. Don’t fall prey to your stakeholder and client demands. You know your project, you know your team, you know their capabilities. Period.

Comment by Albosily on

That’s right…
You can avoid via “Lesson Learned”+”Experts”+”Vendor experiences”+”Team sharing”

Comment by Glen Shirey on

Totally agree with all of it! Here are a couple of things I’ve learned that have not failed me:

1. If I have a shared resource I take their estimate, divide by .75 (at best I’ll get a 6 hr day) and multiply by 2. This is my 50% confidence level estimate, to improve it I look at history as the article suggests. Dedicated resources perform differently and I always look at history.

2. From the Wednesday before Thanksgiving through the day after New Year’s Day you will get exactly two weeks of productivity out of people. This never fails. My old Lab Manager at HP used to call it Christmas Happy A**es. I don’t care how focused you think you have people they are not, and even if they are, they need to work with people who aren’t.


Comment by Michael S. Putzer, PMP, CHPA on

All 6 tips are valid, important and the implied guidance adhered to.

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