I was taught a similar thing when practicing juggling. It was quite a revelation to me. In juggling especially, if you practice until you fail each time you wa

I was taught a similar thing when practicing juggling. It was quite a revelation to me. In juggling especially, if you practice until you fail each time you waste a lot of time picking things back up. Whereas if you practice an amount you are more than capable of you spend more time practicing properly and also spend time learning how to finish properly.