Originally Posted by goran_ace
No offense, but that sounds like tanking to me. If I had ever quit on a practice because I was having a bad day my coach would have told me to never to come back. We all have our ups and downs, but if you want to improve as a player, when you're having a bad day you have to be able to fix it on the fly and/or adjust your game plan and figure out how to work with what else you've got. If you're drilling, you focus on the right things until you get it right. If your backhand is gone in competitive play you need to either need to hit all slices on that side or use tactics to protect that side. You play until your time is up or the match is decided. Finish what you started.
I never knew you could tank a practice.
I believe in practicing hard because at the end of the day you will play the way you practice. But sometimes you need to step away from the court to reflect on your game or simply decompress. I don't see how bad practice really helps your form.
I think it's similar to writing a paper in school. Sometimes you just need to step away from the keyboard, relax a little bit, and then come back at it fresh.