Min-maxing
Also said as Dump stat, Optimising, Theorycrafting
Making one thing as high as you can by making another as low as you dare. Which build is best follows from the formula, so changing the formula changes how people play.
Players will do this whatever you intended, so what matters is what your formulas reward. If stats add together, all your points go in one basket. If they multiply, a balance between them wins.
Say it
“Everyone is dumping defence, because it adds so little. Make damage taken divide by defence rather than subtract it, so that the first points are always worth having.”
Where you’ve seen it
Dungeons & Dragons players call the stat they neglect a dump stat, and for a fighter who plans to do no talking, Charisma is the classic one to sacrifice for more Strength.
Not to be confused with build diversity
Min-maxing is what a player does to a single build. Build diversity is how many different builds survive once everyone is doing it.