When a server comes up to tell me that their guests have enjoyed my playing, I tell them that a manager should be informed of the compliment so it can be recorded in the nightly closing report.
At a purely practical level, that compliment is of no use to me unless it has been documented.
On the other hand, when a workout buddy or another bodybuilder tells me I’m looking swole, that unwritten compliment makes my day and encourages me to keep on track with my fitness journey.
There is value in giving someone a compliment.
There is greater value in knowing how, where, when and to whom a compliment is given.