I just read an article on Life Hacker. I often forget how many good articles are produced on that site. You can read the one I just read at:
Basically, the article aims to show that perfectionism isn't helpful, as the end result will not be perfect. Past a certain point increased effort leads to lessor and lessor gains. I can relate this to grad school- it wasn't enough to get an A on a test, I had to have a 100% (or more if there was extra credit available). While grad school isn't a critical situation, and putting in another hour or so of study couldn't hurt, there are many other situations where those extra hours of effort don't necessarily translate into a better product. But it can contribute to other unintended consequences (like lack of time on another project). At any rate I thought it was an interesting read.