key driver
- catalystAgent enabling change
- forceStrength or compulsion
- engineMachine producing motion
- factorContributor to result
- motivatorSomething prompting action
influence · momentum · impetus · spark · accelerator · propeller · cause · trigger · thrust · fuel · mover · backbone · cornerstone · linchpin · pivot · lever · steering · ignition
causal importance
key driverafterthought
Idea added belatedly
footnote · background noise · red herring · sideshow · irrelevancy