#19 and #20 seems the most common issues I've had to deal with in development.
19. Give estimates without consulting the people that are actually doing the work. When they disagree with the deadline, shrug your shoulders and explain that it can’t be changed and people are expecting it to be completed on schedule. Repeat every time.
20. Break the above cycle when everyone is about to quit. Get estimates down to the hour for every single feature. Assume no slippage. Add features but do not adjust schedule.
19. Give estimates without consulting the people that are actually doing the work. When they disagree with the deadline, shrug your shoulders and explain that it can’t be changed and people are expecting it to be completed on schedule. Repeat every time.
20. Break the above cycle when everyone is about to quit. Get estimates down to the hour for every single feature. Assume no slippage. Add features but do not adjust schedule.