Chiming in on this one:
What I usually say will turn me off of wrestling would these two things happening:
1. The Undertaker's streak ending PERIOD, because he's the reason I started watching wrestling. There's no reason to end it because he deserves to have that accolade on his Hall of Fame plaque.
2. Kofi Kingston getting released, because I have followed his career from the very beginning. Like those who followed Jeff Hardy and CM Punk, I wanted him to be the mid-card guy that rises up to be the top guy.
If these things happened, I'd be sorely hurt and disappointed, and I'd probably not be as connected with the WWE. In the end, I know the exact thing that would turn the channel for me:
Blatant Racism.
When Vince Russo decided to convert Booker T into G.I. Bro, I cut it off. I couldn't take it. WCW was garbage then but I could deal with it up to that point. I only turned it back on once G.I. Bro was done and Booker T went back to his usual name again.
As an African-American fan, there's not a lot to cheer for as it is. Mark Henry right now is the best I can hope for a Black guy being WWE Champion, and that's not gonna happen. Kofi (and maybe Big E. Langston) is the hopeful future, and that doesn't seem likely. So far, I haven't seen a lot that truly offends me (there have been some uncomfortable moments that have walked the line, but nothing that has pushed me away YET) I do love wrestling, and I watch TNA, but I'm not as emotionally invested in that compared to the WWE, which I've watched religiously for 20 years (and followed the spoilers and results when I couldn't afford cable), and even having a heel character break out a racial slur on a face character (not even the blatant ones, even the minor ones) would be enough for me to be offended. It's 2013; racism has no place in wrestling.