Parkinson's Law

If I remember correctly, Parkinson's law states that a task will expand to fit a given time frame, no matter how trivial that task may be or how wide the time frame is.
One will just use up all the allotted time automatically.

Say someone is assigned a task that doesn't need more than 2 hours, Parkinson's law says the task still will not get done earlier if that person is given 2 days, or even 2 weeks.

Reverse may be true, but with a limit: If a smaller time frame is given, in the above case say we give only 1.5 hours, miracle often happens and that task really gets done on time (or at least won't be too far off from 1.5 hours). Bosses are one of the species on earth that constantly abuse this reverse principle: first by cutting the time estimation randomly, then further reducing the time by assigning 'resources' to 'help out'. The reasoning is innocuous at first sight: if a job takes you 10 days, then 2 people doing it will cut it into 5 days. However the underlying assumption is that particular job can be divided into independent chunks, often this assumption doesn't hold, especially in software projects. In fact, throwing more people at a late project will make it later (Fred Brooke's famous quote in his classical text, The mythical man-month).


All in all, these principles are good time management tips that we can try. Give ourselves a tighter margin (without telling the boss, of course), well, starting from tomorrow.