Avoid the Pitfall of Backing in to Your Project Schedule
Beware of developing a schedule by backing in — that is, starting at the end of a project and working your way back toward the beginning to identify activities and estimate durations that allow you to meet your client’s desired end date. Using this approach substantially decreases the chances that you’ll meet the schedule for the following reasons:
- You may miss activities because your focus is on meeting a time constraint, not on ensuring that you’ve identified all required work.
- You base your duration estimates on what you can allow activities to take rather than what they’ll require.
- The order for your proposed activities may not be the most effective one.
One review of a project plan a while back revealed that the project manager had allowed one week for her final report’s review and approval. When I asked her whether she thought this estimate was realistic, she replied that it certainly wasn’t realistic but that she had to use that estimate for the project plan to work out. In other words, she was using time estimates that totaled to the number she wanted to reach rather than ones she thought she could meet.
A project plan is a road map that, if followed, will lead to project success. To have the greatest chance of achieving that success, the following must happen:
- The plan must be complete and accurate (that is, performing all parts of the project in accordance with the plan will actually result in project success).
- The plan must be feasible (in other words, there can be no instances where performing one or more parts of the project in accordance with the plan is determined to be impossible).
- People must believe the plan is complete, accurate, and feasible (it’s not enough that the plan is complete, accurate, and feasible; people must know it and believe it, too).
- People must commit to following the plan (in other words, people must decide to make every effort to perform their project work in accordance with the plan).
- People must make every effort to follow the plan (people must follow through on their commitment).
Basing a project schedule on estimates of activity durations you know are impossible to achieve may allow you to produce a schedule that makes it appear you can finish the project by the required end date. However, as soon as people have difficulty meeting an established date, they’ll stop trying to meet it, rationalizing that they knew before they began that meeting that date would be impossible.