I routinely com new players just for being new or players who screw up, especially if they're obviously very apologetic and embarrassed about it, as a way of saying no hard feelings. I do also com people who just quietly do an excellent job and I have no problems not comming anyone (though I do try to find a reason to com someone), but basically there are a lot of reasons I'll com someone. I'd never com someone sarcastically though, as if I'm actually annoyed with them I'd rather not reward them in even the most trivial way by giving them a com.