One point I'd like to make though is that it's less about the karma itself than it is about the reason that people don't like the question. I could understand why if I was trolling, insulting, etc.
Honestly, I don't care if my karma goes to negative infinity, unless that would automatically ban my account, or something to that effect.
My first year on YC was depressing, as comments that I put a lot of work, energy, effort and thought into would sometimes be downmodded into oblivion.
I would write an expose on Hiring practices we used to have at Netscape, detailing precisely what hiring managers though, and how - and people would downmod me like there was tomorrow.
Over time, I realized, that sometimes it's just a popularity contest. Your comments, even if well meant, may just not be in agreement with somebody elses. I just learned to deal with it - over time you get a sense for the Ebb and Flow - and can learn quite a bit about the community. Don't always consider a downmod to be negative - sometimes it's just a reflection of what other people think - not a reflection of your comments value.
"Resist complaining about being downmodded. It never does any good, and it makes boring reading. "