I'd like to know what is your approach towards repertoire and maintaining it.
I never used to worry about it. I used to happily learn one piece or exercise after the other and forget the previous one in the meantime. I used to live with a "repertoire" of 1 piece of music at any one time. Then I got tired of this, especially as I started to learn pieces of music I really liked.
Last December I started to play every day the pieces I wasn't learning. Initially this meant learn a new one and play maybe another one or two to keep them in my muscle memory. This is now a total of 8 pieces, too much for a single day, so I've put them on a 3 days rota. However I feel I'm not using my time effectively, because for the sake of not forgetting them I am not improving any of them and I've also started to lose interest in one, but I am reluctant to letting it go. The only piece of music I feel I'm progressing, naturally, is the one I'm currently taking lessons on.
Am I wasting time with the rest? Should I only keep 2-3 pieces in my weekly routine? My practise time is limited every week and I fully realise that playing badly through a piece just for the ske of remembering the notes isn't practise, it is actually counterproductive. So, what do you do? do you set them aside knowing that it won't be too hard to pick them up again if you wish too? I find it frustrating when I need to re-learn a piece, probably because I don't sight read. I normally read a measure at a time and memorise it, then move to the next, until I can play the full piece from memory.