the goal for our kids to learn piano, as I said, is not to make them virtuoso, but to provide a chance to have a panoramic view of music. So for most people, there's no point to make your kids working 24/7 on piano. From my point of view, to entertain oneself (and maybe guests occasionally), and understand the structure of music in general, is good enough to be a goal to learn piano. And to reach that humble goal is not hard at all.