I've been a consultant for over 8 years and during that time, I've lead a few projects, been on a few and helped to clean up a few more.  I have also been a part of some failed projects, which honestly, if you're going to fail, fail big.  Anyway, during my time I have created a set of rules that I carry with me on every project.  These rules are kind of like the 10 Immutable laws of security, they transcend all technology.   I decided to share them in case others want to share their rules or comment on mine.  Enjoy!

1. If you say it's easy, you have just signed up for that work
2. If you say it's done, then it better be Done.Done
3. If you break the build, you buy doughnuts
4. You are not allowed to estimate unless you are willing and able to do the work.  Willing and able are different, see rule 5 and 6.
5. If you're not a developer, don't act like one.
6. If you're not an architect, don't act like one.
7. If you don't know, are unclear or have questions, ask.
8. If you built it, you're not allowed to say it works.  "It works" is for the unit tests, test scripts and testers to decide.
9. If its broken, fix it.  The team is accountable.
10. If you didn't pay for it, it's not yours.  Don't act like it.