I get asked a lot by Web Project Managers about how to accurately produce task time estimates. Let's face it, having a team member, let alone the entire team, estimate task time is not easy. This is, especially true if your team does not have a lot of experience with the type of project you are tackling.
Task estimations are important to a Web team's success. If your team is struggling with accurate task estimations here is the method I've used with success to improve our predictions. (Note: you may never nail this every time, but improving a little on each successive project - that is entirely doable.)
1. First, explain to the team members everyone is going to use time tracking software. (If you are already doing this - great! Many teams don't use this software.) Often team members worry the information will be used to evaluate performance, but that is not the point at all. They don't have to share the information collected with anyone. (Okay - they do have to report when the task is complete, but the point isn't to collect info for performance ratings, it is to allow the team member to keep a log of task duration times for their future estimate work.)
2. After the project launch during lesson learned discusions the team reviews any insights they gained during the project regarding the accuracy of their task estimates. Most are amazed to find initially how far off they were in their estimates. Usually, they underestimate the time required - resulting in tight deadlines and undercharging for the project.
3. As team members begin to compare previous estimates with actual times, they realize why they over or underestimated their times. Task estimates usually become more accurate for succeeding projects, for most of the team. Some team members are eternal optimists or pessimists - they can't help it. Their estimates are always either too short or too long.
4. As Web Project Manager, figure out which team members are always predicting their task times are too short or too long, then adjust their estimates for them, adding more or less time based on their history.
5. If after several projects a team member's estimates are still all over the place, have a discussion to see what might be the cause and if there is any way as Web Project Manager, you can help them improve their accuracy, or if the problem is that their work on each project is so unique there is no way to estimate the work time. If so, build in a bigger buffer for their work, but don't be too surprised if after the discussion their time estimates improve. You may just have someone who wasn't using the time tracking software.
This method has worked well for me. What has worked for you?