When an assistant coach leaves, you look for explanations. Covering West Virginia, I’ve got a lot of experience. Whoever replaces the departing Brian Mitchell will be the 24th assistant coach to work for Dana Holgorsen. But we’ve learned through the years and the transactions that some moves can make sense.

Bill Bedenbaugh worked for Mike Stoops at Arizona. Jake Spavital got a major career boost. Shannon Dawson got to call plays. Tom Bradley was back in charge of a defense. Daron Roberts and Erik Slaughter and Damon Cogdell were not great at what they did.

Mitchell’s exit, on the surface, makes the least sense, which may in turn make some sense.

Mitchell was not fired or forced out. This is not about a contractual or a performance issue. But, as hard as this is for me to say as someone who likes Mitchell on a personal level and cannot know what’s in his heart or mind, it’s not about a better fit, either. Holgorsen and Mitchell are tight. Tony Gibson is a big fan of Mitchell’s work with his players on the field and off of it. Those two pressured Mitchell to stay before and after Mitchell visited Virginia Tech Wednesday.

When I was told today about Mitchell, I honestly thought Mitchell was going to Virginia, because he worked with and for new Cavaliers coach Bronco Mendenhall at BYU.

Nope. Virginia Tech.

This isn’t a move up, like Spavital or Robert Gillespie, who’s been a big deal at Tennessee. Sure, working for Bud Foster is a pretty good deal for an assistant, but Mitchell is 47. He’s not a young up-and-comer who needs to sit beneath the learning tree.

And here’s the — the — connection to Virginia Tech, which is still a fine program likely in very good hands with former Memphis coach Justin Fuente and Foster there to show him the ropes … an arrangement that always works. Always!

When Mitchell left Texas Tech, he was hired as the cornerbacks coach at Memphis. You will not find this in his biography. I didn’t even know it until someone told me Thursday (which underscores how this move perplexes people).

Anyhow, Larry Porter, who then was the new Tigers coach, hired Mitchell to be his cornerbacks coach. Mitchell spent a week or so there and got to know Galen Scott, who was newly hired as the linebackers coach. Then Ruffin McNeill, who had been the Texas Tech defensive coordinator when Mitchell was the cornerbacks coach, was hired at his alma mater, East Carolina. He hired Mitchell as his defensive coordinator.

Mitchell spent three seasons there. Scott stayed at Memphis through this past season and followed Fuente to Virginia Tech, where he’s the assistant head coach who runs the defensive tackles. He is, quite likely, the team’s next defensive coordinator.

So, there you have it.

But trust your eyes. Dana Holgorsen has two years left on his contract, and there is no indication that’s changing. Only offensive coordinator Joe Wickline and defensive coordinator Tony Gibson have contracts guaranteed for beyond this coming season. (That’s according to a Monday’s response to a FOIA inquiry.) WVU gave new safeties coach Matt Caponi and retained special teams/defensive assistant Mark Scott one-year contracts. Ron Crook, JaJuan Seider, Lonnie Galloway, Bruce Tall and Mitchell were not — or have not been — given extensions to cover them beyond 2016.

Was Mitchell poached? Was he offered and did he embrace a better career opportunity? It’s hard to know for sure today.

What I do know is it doesn’t look great for the football program, which has talked about positive offseason momentum for the first time since after Holgorsen’s first season and which nailed down a promising recruiting class but has also waved goodbye to three assistants and seen no noticeable infrastructure improvements.

This means something, right? Is eight wins enough and/or do decision-makers like the track the team is on at the moment? Is what’s happened not enough and the same people think more has to happen?

I think that regardless of an answer to either question, there’s a comment. WVU has to do something.

If eight wins isn’t enough and WVU aims higher, the house should have been scrubbed clean or the program should have been enabled to get to where it needs to go. If eight wins is enough, the program should have been rewarded and then enabled to keep things in place and keep the momentum moving the right way. There’s no such thing as doing nothing, because even if the plan is status quo, it creates work on the other side.