The rewarding part of being a mentor is hearing that your advice was both used and went well. If you're being mentored or even casually chatting to a friend, let them know how you got on. Closing that loop builds the relationship and keeps people engaged with your problems, meaning they'll likely help you more in the future.
Heads up: As with any terse bit of advice, there will be exceptions of course, and subtleties and nuance that can't possibly be captured in a Byte of Wisdom. This has been what I've experienced, I'd love to hear yours in the comments too!
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