Found over at the very good Project Connections website
1. Everything takes longer than you think (sometimes a lot longer)
2. Thinking about everything takes longer than you think
3. Project Managing and leading a project team is a FULL TIME job, and then some
4. Software Engineers are always optimistic (generally REALLY optimistic)
5. Schedules are (almost) always wrong
6. If you under-estimated an early task when you wrote the WBS (schedule), you probably under-estimated middle and later tasks. Revisit the later phases of the schedule as early as possible when you discover early phase schedule (estimate) errors
7. Business types (upper management) REALLY do use your estimates for planning. For example, head count, money, customer deliverables, shipping dates, ordering materials, scheduling manufacturing lines, advertising timing, etc. Be able to express your level of confidence on various estimates when you provide them to others
8. Initially, a good schedule estimate is 80% confidence for near term deliverables, 60-80% for long-term deliverables. Revisit the schedule and revise your estimates after the Initiation Phase (Kickoff) and again after the Design Phase to improve on these early confidence levels
9. Don’t let yourself be bullied into committing to something you cannot achieve
10. Don’t bully someone else into committing to something they cannot achieve
11. Notify “Need To Know” people AS SOON AS POSSIBLE if there is a significant problem or potential problem in meeting the schedule. Remember that there was a certain degree of optimism in the schedule originally. Note: It's an art to not over-do this
12. Let team members know that you, the project manager, expect early notification of schedule problems as a courtesy. You decide on the severity or risk of the problem and its impact to the schedule, what actions to take, and what contingencies are appropriate
13. Most people’s estimating skills improve with experience; some don’t
14. Learn your own estimating flaws and compensate for them. Then learn the flaws in your new estimations and compensate for them. Repeat continuously while employed as a project manager
15. Learn others' estimating flaws and learn to compensate for them. Mentor them on improving their flaws and then compensate for their improvements. Repeat continuously while they are on your project team
16. In some environments, some people are hedging their estimates, some people are expecting them to hedge the estimates and some people are doing neither. It’s an interesting problem to get all of them to stop this behavior and have people give honest, best-effort estimates. Laws 14 and 15 are useful for dealing with this variability while you are working to get your team members to be more honest with you. Laws 13-16 are part of the "people aspects" of the project management job - like it or not, we have to deal with these "real world effects" on the projects we manage
17. Be wary of anyone who wants 100% confidence in an estimate. 90% confidence is an exceptional human achievement for any complex task, even with extremely good data
18. Look up the word “estimate” in the dictionary. You may find it useful in a meeting
