There is a term in kendo called hikitate geiko. I won’t get too technical, but in essence, it is an attitude employed by a senior who spars with their junior that helps elevate their skills. It is more difficult than it appears, because if you make it too easy for them, they don’t improve, but if you make it too hard for someone, they won’t learn anything either; and at the same time, you yourself won’t benefit from the spar. By practicing good hikitate geiko, you are able to elevate your partner’s skills, but at the same time, refine and perfect your own technique.
I find that this attitude is beautiful in every aspect of life, and isn’t easy to accomplish; I think this is a huge green flag when someone does that well, regardless of the situation or context.