Jason Garrett spent 13 seasons as an NFL player, including eight years (1992-99) with the Cowboys.
Jim Harbaugh was a starting quarterback for a while, but he's certainly received more attention for his coaching success than anything he did as a player.
Guys like Jeff Fisher, Leslie Frazier, Jack Del Rio and then some career backup guys like Gary Kubiak and, yes, Jason Garrett - they were good players, but not really superstars.
It takes a different mentality to become a coach.
You see it in other sports as well. In the NBA, there aren't many great players who go on to coach. There are some - Larry Bird and Isaiah Thomas tried it. I know there are others as well.
Great players found a way to get the job done because they were great. That's what separated them from the rest. Sometimes you can't teach that. It's not just one thing.
Look at football, basketball and baseball. A lot of former players are now coaches or managers. But most of them were either role players or even backups, and rarely a superstar.
The point to all of this - every coaching staff needs a healthy mix of everything.
And it looks like the staff Garrett is putting together will have that. He's got some high-strung, intense coordinators like Ryan and DeCamillis around him. But one thing that seems pretty clear, Garrett is looking to add a few former players to the mix.
Now, let's just hope it gets announced sometime soon.