He's never making it here.
Sorry, but that's just how it is.
You don't need another season to realize what's so obvious about him. He's never been motivated enough to develop into the player he potentially can be. Whenever I see him play, I see the same faults in his game. Sure, Valverde is not the best manager to develop a player like him, but you cannot blame Valverde for Dembele's lack of effort, him being unable to make easy passes and standing at one place instead of moving off the ball.
I've been a big supporter of his, like you can see in the earlier pages in this thread, but I've given up on him and so should most of you.
He won't be the first extremely talented player who's failed to make the big step.
Alexis Sanchez was a force of nature in Udinese, but in his club career he failed to truly make it at Barca and then went to Arsenal. I can see a similar career path for Dembele.
I understand that a lot of you don't want to accept it, he's a maverick, exciting to watch when he's on fire, and we invested a lot in him so a lot of you naturally want him to succeed, but I don't see it happening.
He's gone after this season.