He said something post-interview after the Finals Game 5 that his Mama taught him. Something like not being hyped when you are up and not too down when you fall. That's how I understood what he said.
Jokic won't celebrate too much and he won't also feel down even if he loss. That's what I see with him and I think it's a good thing. He is just moderate, not in panic, not overexcited so he won't do anything stupid in his life. That might also be the recipe for why he is good when he is on the basketball floor. He is just calm.
Excellent teaching by her mother. I believe it has something to do with psychology. Similar to what I've been trying to do for the past three years, but not quite there yet. I do this to keep myself from overthinking, to stay calm, and to be more focused, especially when making decisions about different stuff and it actually works, and I feel better every time I did it no matter what the result is.