You guys aren't factoring in that sometimes players just don't wanna stay & are ready to move on.
People always get beside themselves when players leave early, but the reality is, you shouldn't want any player that doesn't want to stick around to come back for another year. All they end up doing is driving the locker room down. And tbh, there's nothing that can happen that will change the trajectory of the outcome. If he wound up as an UDFA after his Junior season, the reasons that lead to that happening will still be there his Senior season.
If he's got bad work ethic as a Junior, he's gonna have it as a Senior. If he takes plays off as a Junior, he's gonna take plays off as a Senior. If he's fat & lazy as a Junior... You get the gist.
The guys who leave early are doing exactly what they're supposed to do.