The pot challenge is one group is they get graded just on number of pots made vs. the other on a single pot they can submit. The group trying to perfect one pot ends up making worse quality pots than the quantity group because the quantity group ends up getting way more practice.
That anecdote gives me lots of hope. I hope it's accurate! :)
One thing to note about the pot challenge - it works because making a pot is a physical skill that improves with repetition in a situation where mistakes are really obvious. If you were to apply the same principle to something else it might not work at all.
If you just write a huge amount of code rather than examining what's good or bad about code you wrote, you'd probably end up writing the same bad code over and over again. Seeing where improvements can be made is sometimes really not obvious and can feel like you're going backwards. For example, learning where functional programming applies instead of writing a class for everything. You need to be able to understand why something is better for simple repetition to work.
That anecdote gives me lots of hope. I hope it's accurate! :)