It's about the number of orders you can make for individual or small groups of units, e.g. split attack orders so each part of your army blows one enemy unit in

It's about the number of orders you can make for individual or small groups of units, e.g. split attack orders so each part of your army blows one enemy unit in one shot thus not wasting DPS. The best example is Brood War pro player Jaewong who literally had 70+% win rate in a rock-paper-scissors called Zerg vs Zerg.