1. He Wins Football Games
Sometimes it really is that simple. In his first head coaching job at San Diego State, Harbaugh went 29-6 over three years. Then he went to Stanford and went 29-21, including an Orange Bowl win. At Stanford! He moved on to the 49ers and immediately proceeded to go 44-19 in four years, winning one NFC Championship and making one Super Bowl. His (presumably) final record at Michigan was 89-25 with a National Championship. 'Unbelievable' gets thrown around a little often, but the amount that he wins everywhere he goes is quite literally almost unbelievable. He would have the Falcons in the playoffs, and if history's any indication, it'd probably happen pretty quickly.
2. You Wouldn't Need To Worry About The College-to-Pros Transition
For a while in the early- and mid-aughts, jumping from college to professional was all the rage. Every NFL owner wanted to hire the next great young offensive mind out away from their Power 5 program, and it, uh, didn't really work. Chip Kelly, Kliff Kingsbury, and Urban Meyer all names that immediately come to mind. Even Nick Saban's NFL record leaves a ton to be desired. But Harbaugh's an outlier – he's already proven that moving between college and the pros isn't an issue for him. When even the most successful college coaches consistently seem to struggle at the NFL, Harbaugh doesn't. That's not nothing.