One of the things to remember, epically about the work place is that it costs other people time ( and the company money ) to have to go through a sub that is not commented. Just to figure out if it does what you want. When many people work on a project, epically a complex one that is potentially days of man-hours wasted because the original developer didn't feel it was important (or just plain didn’t think about it) to comment his sub. This can also lead to other things like many subs doing the same task (because other people didn't want to figure out the code) etc... As ridiculous as this sounds, I have run into it several times at my current job.
Sorry one of my pet peeves is not commenting code other people will be using.
Josh