When I was active on SO I did often see unwelcoming behaviour. Closing questions as being dupes or offtopic, with no explanatory comments, was the most common

When I was active on SO I did often see unwelcoming behaviour. Closing questions as being dupes or offtopic, with no explanatory comments, was the most common thing. Infuriating too (and not only to new users) was the proliferation of bad edits, clearly undertaken by clueless people to try and amass points. More of an irritant to me was the generally noisy and poor-quality content. I will only follow links to SO now in areas where I know enough to be able to filter for quality myself (usually it's wanting). From my perspective, the gamification schtick is a failure.