Leach isn't leaving Pullman. Dude is living the life there. Loves the Pacific Northwest and expectations are super-low at WSU. They were picked fifth in the Pac-12 North this year and were a screwed call at USC (re: non-targeting on Minshew) from finishing 11-1 overall and 8-1, which would've had them winning the division and going to the Rose Bowl against Ohio State.
Granted this was all the result of the Gardner Minshew transfer and they'll fall way off next year—but there's a reason the dude didn't jump when other schools have come calling over the years (re: Tennessee, etc). Likes to be that big fish in a little pond, opposed to dealing with the scrutiny he'd get at a bigger program. Check his track record and prove me wrong. There's a reason he's never taken a big job in his career and continues to fly under the radar.