[kbknight]

I would add Rob Henderson's "luxury beliefs." But also...

I think the bloggers account for "Parkinson's Law" is too simplistic. If it were just about procrastinators, it wouldn't be as useful. Deadlines (even artificial ones) work because we can always make a system a little cleaner, a little more efficient, with fewer bugs, well past the point where that work has any value.

[ldx1024]

That would mean the software would work well. I run that explanation against what I see in practice and in general it is not a good fit.

Along with procrastination (which might have noble motivations) an additional much simpler answer is that people just want to do the minimum they can get away with.