Programming is a task which involves doing things that haven't previously been done, in detail. There are many unknowns to be contended with. It's most producti

Programming is a task which involves doing things that haven't previously been done, in detail. There are many unknowns to be contended with. It's most productive to get a high/low range of completion dates, and try to manage so that in the long run, the probabilities of each end actually balance out. Finishing far sooner or far later that the bounds should be a rare thing, though it won't be initially. They should get better over time. Giving programmers the ownership of their work, and understanding the challenges they face is half of management. The other half is setting expectations to upper management. The other half, is managing the conflict between the other two.