It's pretty much inevitable that someone, somewhere will eventually get mad around you for whatever reason and direct it your way. When that happens, it'll be easier on you if you've already anticipated the possibility and worked a bit on dealing with it.

Trying carefully never to get anyone mad at you probably won't help much; some people even find that annoying.

The way I see it is, if someone's going to be mad at me no matter what I do, I'd rather know I did the right thing. It seems to bother me a lot less to have someone mad at me if they're unable to tell me what I could've done differently.