pass-along favor 

Where you "skip a step" when doing something nice in return for the kindly assistance of someone else.

The classic pass-along favor in its simplest form involves three people (Persons A, B, and C), and works as follows: Person A assists/accommodates Person B in some way, and so Person B wishes to return the favor. At that particular time, though, Person A does not have a need for anything that involves the skills/abilities that Person B happens to possess. Person A, however, either owes Person C a favor or is tasked with providing Person C with frequent care/assistance, and so Person A requests Person B to do something nice/helpful for Person C, thus saving Person A from having to assist Person C on that occasion.

pass-along favor by QuacksO July 15, 2018