Maybe I shouldn't have put the 1000 in the title because, to be fair, that is what she quotes her teacher. Her short video's main point is beginners tend to not doing enough repeats slowly but rather increase speed prematurely. That is something I am recently noticing in my own practice. Certain spots stays a bit "wobbly" until I force myself to set my metronome to ultra slow and practice just that spot.
Of course I won't and can't do it 1000 times. @Seeker has been drilling me the Molly Gebrian method of 3x without mistake, do something else, then another 3x no mistake. I also find alternating between slow tempo and target tempo seems to both help and somehow less boring.
But the more I think about the 1000 times number, the less ridiculous it feels. Take things as simple as scales, would you say you have practice it 1000 times? If it take far less than 1000 times to master a scale, why would any one keep practicing it? On the other hand, nobody is trying to practice a scale 1000 times in as short time span as possible and call it done. It's something to do a few times a day but keep doing for years.
Then, for passages or patterns that's difficult, either to pros or to beginners, it may very well take many many many times to fully master. But because patterns recur in many pieces, we don't need to be stuck in one piece forever. Instead, as we learn new pieces, we could be still be repeatedly practicing many common patterns until we reach the quantity and achieve the quality for each one?