Maybe I'm really getting old, but a lack of inspiration or, as someone said to me a while ago, a certain indifference seems to be a problem with a lot of younger pianists these days, at least in the "iron repertory" as we say here (Beethoven, Mozart, etc.) Can't think of any names right now, but I've bought quite a few CDs by younger players and subsequently got rid of them because of it. They're often technically impeccable, but something seems to be missing from their playing.