olemus
Merriam-Webster:
3a : BENEFIT, GAIN
especially : benefit resulting from some course of action
a mistake which turned out to our advantage

collateral advantage-- kaasnev kasu
incidental advantage -- kaasnev kasu
mechanical advantage -- võit jõus
mutual advantage -- vastastikune kasu

https://en.wikipedia.org/wiki/Mechanical_advantage

vt ka
- kasu (1)