From Reddit user bradlee92 …
“It doesn’t matter if you spend 1000 hours practicing if you’re doing it wrong, all you learned is how to do it wrong.”
From a tennis blog …
“Practice doesn’t make perfect. Practice makes permanent. Perfect practice makes perfect. So every time you repeat an action, right or wrong, you will find it easier to repeat that same action, right or wrong.
Practicing a bad shot will give you a better bad shot, but you will never look like Roger Federer.”
Life's Best Advice 