If you're an athlete, fair enough. You need your muscles to suffer for you to make it to the top.
But as a learner? Different story. Pain, in the form of feeling bad about our mistakes, just gets in the way.
Babies and sportspeople
Think of babies learning to walk. They fall over constantly, but they don't feel upset or embarassed about it. They just try again.
It's the same with top sportspeople. They might feel a bit frustrated with a slower laptime in practice, but they don't want their coaches' praise. They want to know where they went wrong. Is the negative feedback painful? They keep asking for it.
Here's a personal example
About 15 years ago, I was taking part in a workshop for professional speakers. I had crafted and memorised my presentation thoroughly, using the techniques of oratory I had studied for years. I felt confident and pleased with the result.
There was a pause and one of my speaker friends commented, 'It was good, but a bit like a dissertation'.
It was disappointing, sure, but the most valuable feedback I've ever received and a turning point in my speaking career. Since then, I've ad-libbed in conferences. I'm far more interested in engaging audiences than being word perfect. It's like a one-way conversation.
How much difference did the disappointment make to my speaking career? None at all.
How much difference would praise have made? The same. I wouldn't have changed a thing, just gone on making dissertations, possibly word perfect, but in my own little world while the audience wondered what the dog was doing at home.
Welcome the negative
Negative feedback is more valuable than positive, but it doesn't have to be painful.
Let's accept that setbacks are opportunties and just a normal part of learning.
Let's decide that we don't need to show the world that we are successful performers already. We may still feel frustrated and disappointed by setbacks - but we can choose not to feel crushed, humiliated, or tempted to give up.