Tim Stone asked: New users often are not accustomed to the Stack Exchange system, and sometimes struggle to present themselves properly, either in the way they use the site or their attitude. How willing are you to work with "problematic" users, and at what point do you decide that someone isn't worth the effort?
Rory Alsop answered: I have only had this a handful of times, and my approach is: try to educate through comments first, then through private messaging; then suspension. One of those users did supply good content, but was very argumentative, so I just remained patient and tried to escalate through those steps slowly. The other had very average content, so I was probably a bit less polite. But he too was worth the effort. If people want to contribute, I want to support them at being better contributors.
Sklivvz answered: Oddthinking prepared a wonderful Welcome to New Users page, that's the first step. For more problematic users there are different steps, contacting them in chat, via mod mail and finally successive levels of suspension. Fortunately we've had to use these tools a limited number of times since the site's beginning.
Fabian answered: I don't expect new users to immediately know our rules, but I expect them to be able to learn and accept them. There's a huge difference between a user adjusting to the Q&A format and our very specific rules, and a user just causing trouble. If there is no change in behaviour after explaining the problem to them, there's not much more moderators can do except to clean up and suspend if necessary.
Fabian continued: I'll add that very, very few trouble users are responsible for a completely disproportional amount of moderator time spent.This amount is completely unsustainable if we get more of those users, so we have to limit ourselves there as we don't have unlimited time.
Sam I Am answered: I think comments are best in that case. I try to be welcoming but explain our rules are a little different. Most people are posting in good faith and they just need a nudge. What point is it not worth it? If it is clear they are not in good faith.
Larian LeQuella answered: Hmm, I've never "given up" on a user (although I will freely admit human bias on some). Again, edit is a powerful tool, and that can be used to salvage questions and answers. Again, I try to make it a collaborative effort as opposed to my unilateral view on the situation.