The best measure of influence is what people carry forward after your involvement ends.

What you did while present eventually fades. What persists is the practice someone kept, the standard they now hold themselves to, the way of thinking they took with them. That residue is the real measure, and it is invisible until well after you are gone.

Ask what you would want someone to still be doing in three years because they worked with you. Then teach that explicitly rather than hoping it transfers. Most of it does not transfer by osmosis.