This account has been enabled since 2006, but I have so rarely and sporadically used it that I'm still unfamiliar with most of Wikipedia's underbelly.
I think I've just been unlucky in this, but of the very few articles I have tried to contribute to, I have run into people who are much more familiar with Wikipedia's usage and policies and seem to know how to manipulate it to their advantage.
The first situation, was a whitewashing of a disgraced company and executive, which used notability guidelines to have their entry removed by slowly and persistently removing content from the article and then requesting deletion. I did not have the patience to fight this uphill battle. I believe the page eventually returned, but I haven't bothered to revisit it.
The second was my own fault, for getting into a silly editing war over a difference of opinion.
The third time, I tripped over a bureaucratic-minded editor who had me jump through an enormous amount of hoops for a single source reference edit I had added (and he removed). Only for me to realize partway that he had been going on a mistaken assumption about the source all along. That didn't stop him from piling on more and more links to Wikipedia guidelines and his unwavering interpretation and adherence to his assumptions.
I love reading Wikipedia, but I think it's going to be awhile before I edit again. It's been incredibly exhausting to do so every couple of years or so.
For anyone that's taken the time to read this, please support the everyday contributors to this site. I believe they are far more valuable to its content than the obsessive few.