Yes, mistakes happen all the time. One aspect of the aviation industry that I have always noted is the reluctance to adopt this as an excuse for failure. When a pilot pushes Button X instead of Button Y, it isn't just chalked up to pilot error. Somebody asks why Button X and Button Y are arranged right next to each other to begin with. Why was a situation created in which "pilot error" becomes so easy? Then things are changed so that such pilot error becomes harder and less likely.

It's an admirable thing when somebody has to go out of their way and go through some contortions to make critical mistakes.