There is probably nothing that bothers me as much as when people don't accept answers to their question and give no explanation whatsoever. Did you find an answer by yourself? Post it! Did you find all answers unfit? Leave them a comment, so they can know what you're still missing.
There really is no excuse to just leave them sitting there for more than, let's say, a week. Any more than that's just being a dick to the people that went out of their way to help you, as well as harming SO as a whole.