"You will not master mathematics by playing a mathematics game if you are dumb as a rock, or if you are naturally intelligent for that matter. Mastering such skills takes decades. And it is hard work. You have to do a lot of boring shit. And it is not always clear, the way forward. You can spend a lot of time on a thing where you later find out that most of your efforts didn't have much point, after all. It can become very tempting to give up, and if you aren't dedicated that's what you will do. Intellectual achievement is brutal and unforgiving, because you are dealing with reality and not a fantasy that someone else has created for you."

This, this, a thousand times this.

The worst part about it all is that because you only ever see other people's successes published in papers, textbooks, and etc., it can seem from confirmation bias that no one else makes mistakes or even really struggles with mathematics, but of course the truth is very far away from this.