I get a lot of questions about what to ask when choosing a grad advisor.
Ask the trainees how often they hear "thank you" and "good work" when they try something difficult.
A thread

Everyone who gets into grad school wants to succeed, and has a track record of working hard. Most of us find fulfillment in working hard and being appreciated.

I promise you that there are advisors who know how to do this. Advisors who say "thank you" when you try. Advisor who say "good work" even when it's not perfect.

We hear a lot about how grad school can be demoralizing and traumatizing. I think we need to also hear how great it can be, because it helps us reset our standards. "Grad school is hard" is too often used to ignore justified complaints from students

So, ask how often the advisor verbally appreciates and celebrates not only the successes, but the efforts. Don't ask whether or not they do it, ask how many times per month.

It is okay and reasonable to need some external gratification in grad school, especially from someone you look up to. And they as a leader need to realize how important it is to your work ethic that you feel valued oh, and that you are trusted to be doing your best work.

Tldr: a decent leader doesn't break you down - that's the bare minimum. But, a good leader actively builds you up.
It's okay to need a good leader in grad school.