Triggers are almost the opposite of primary variables. While primary variables tick up or tick down, always ready to be corrected and for which compensated, triggers are "all or nothing" events.

When studying what an expert knows/does, the question is, "what are events that if happen are (at least temporarily) irreversable and that change the dynamics? "

In the game world, this might include your characterer, after losing health (a primary variable), finally dies (a trigger).

• In the real world, after working hard to improve productivity (a primary variable), you might get a promotion (a trigger).

• After working hard to figure out a solution with a perspective client (a primary variable), you might get the contract (a trigger).

• After building support for your bill (a primary variable), you might get a favorable vote (a trigger).

Of course there are bad tiggers as well: losing a big client, or having a facctory break down.

Triggers and primary variables go hand in hand. Talking about one without talking about the other misses the point.