Nobody ever got better by being bullied, and that includes being bullied by themselves.

Cruelty does not teach anyone anything. It makes people smaller and more careful, and careful people stop trying things. That holds when it comes from a hallway, and it holds when it comes from inside your own head, in the voice that calls you an idiot over one missed question. Harshness can feel like having standards, but mostly it produces flinching.

Listen to how you talk to yourself after a mistake this week. If a friend said those exact words to you, you would notice immediately. You can keep a high standard and say it plainly, without the insult riding along.