What makes the Chiefs so clutch and always being able to get those nail biter wins?

Obviously they have Mahomes but I don't know what it is exactly that makes them so great. You just know you're getting into a dog fight, the margin for error is small, and you know it's gonna come down the wire and the Chiefs are likely to pull it off. Rarely do they ever choke or get beat handily. That's how good they are, I just expect them to win every time.