What’s the one quality that makes a great Engineer/Chauffeur/Apparatus Operator?

Building on the last thread where we talked about what makes a great rookie, let’s take it up a notch.

When it comes to the engineer seat (driver, chauffeur, AO) What’s one quality that separates the great ones from the rest?

Take “safety” off the table. That’s non-negotiable — it’s the baseline, not the bar. I’m talking about the next-level trait. The one that makes crews say, "Thank god, he's at the panel today."

Is it precision? Calm under pressure? Mechanical knowledge? Being one step ahead or something else?

Do the traits that make someone a great rookie translate into being a great engineer — or is it a whole different beast? Does the backseat mindset lay the foundation for front-seat performance?

Let’s hear it — what’s that one quality?