I don't really understand this! It's like some kind of a curse or a disease or something!
hello Little Tune! You are being too hard on yourself. It happens more often than you think. Enzo, whom I consider to be an advanced student of the piano regularly has mistakes despite the fact that he has practiced the piece a "thousand times". But he tries not to let these mistakes bother him that much despite his being a "perfectionist". He just moves on and considers it part of the learning and growing process. And over the years, partly because of that attitude ... he seems more relaxed while playing and commits less mistakes. If you listen intently to some masters during live concerts you may pick out a few mistakes .... which a s a whole does not diminish a bit the performance. I am sure as you advance through the years this problem will diminish. So ... not to worry ... it is not a disease and it will diminish with time if coupled with the correct frame of mind. GOOD LUCK!!
The only other thing I'm thinking of is getting more control. Easier said than done though. Control being where you understand the piece enough to where you can change it if you wanted to. Change a chord, change the melody. Know exactly what's going on in the piece for that the whole time. If the piece is ingrained and learned long enough ago that you don't have to think about it, I think there's something that can happen where you just start it off and then watch your hands play. Not necessarily bad, since that can glue it together. But then the mental game comes in where you don't want to think about it too much in case something you're thinking influences the 'autopilot' the wrong way. So maybe analyzing the piece more would help.
For me at least it was almost always due to a lapse in concentration -- my mind (which is incorrigible, but I have to live with it) would momentarily think of something else. It might be the audience (for me, the congregation). It might be that devastating thought -- which verse of the hymn are we on? It might be what I plan to buy for lunch on the way home. It might be... but always a lapse in concentration.If you can work on two things: ignoring the audience completely and pushing the rest of your life out of your mind; think only of the piece at hand -- it will help. Some. So will just doing it more.And don't worry about it. We all make mistakes!
I wish i could say i always make ONE big mistake in my recital...