An Editor's Self Assessment

It's after nights and papers like these when I really have to wonder how I can enjoy editing.
I mean, what kind of sick fuck puts himself through such a masochistic process? More often than not, the essays you do get are fairly poorly written, with sentences that aren't actually sentences and words repeated over 30 times in a four page paper. The round-about arguments made start becoming jumbled in your brain, and by the time you reach the last page, you hardly want to make any more marks on the page; your pen is probably out of ink already. And afterwards, you have to confront the individual in question about it, all the while needing a positive frame to put the crooked, wrinkled, ripped picture in.
Sure, not all the work I've gotten is that rough, but those mostly come from other English majors, and even then we all make mistakes. Hell, you can probably find a few errors here as you're reading. So, why do I do this anyway? Why do I want to spend the rest of my days studying huge manuscripts from cover to cover ins search of any and every error within?
To be honest, the answer's pretty simple; I'm helping other people. At the end of the day, I'm changing someone else's life for the better. They'll get a better grade on that essay because of the edits I put forward, or they'll rework their story in a way that makes it more comprehensive to a general audience. Even if they don't take any of my advice, at least I've gotten them thinking about their work and jogging their brains with all sorts of ideas of where to go next with whatever they may be writing. Can it be grueling? Yes. But the pay-off, while not material, is clear; meeting new people and making their lives just a little easier, not to mention more experience with editing in general. The best kind of reward there is (though money is nice too :P)
Ironically, I cannot stand editing my own work for whatever reason... But perhaps that's a thought for another evening.