Barcelona cannot (yet) throw in the towel with Ousmane Dembele. They should not do it. Because Dembele's failure would also be Barça's failure. A resounding failure... A signing not working is one of a number of variables that exist in football. Not everything goes as planned. Not everything is always as you imagine. It's the same with players.
But making a mistake on a deal worth 20, 30 or 40 million euros (like with Arda Turan, André Gomes or Paco Alcácer, to give some recent examples) is not the same as messing up a deal worth 105 million (plus 40 million more in bonuses).
Dembele's the club's second most expensive player, after Philippe Coutinho (120 million plus 40 million in add-ons). Neither has yet justified their price. But while the Brazilian (beyond his performances) is a disciplined footballer, totally integrated into the team and club dynamic, the French forward is squandering his short career with a lack of professionalism and bad company.
Barça must stop, however they can, the devaluation of Dembele. It's proving meteoric at the moment. The first thing they have to do is look for a reaction. Make him realise that the opportunity of a lifetime is disappearing. Any 21-year-old kid would die to play at Camp Nou. Dembele has the chance to do that. He has the qualities to do that. But he doesn't want to. Or that's what it seems given his unprofessional behaviour.
Punishment (leaving him out of the squad) is the first option. But it's not the only one. Nor the definitive one. The solution is difficult. Very difficult. Above all, because the interested party seems to be the least interested in finding the solution. Still, everything inevitably comes down to dialogue. And persuasion. And if, finally, there's no reaction, find a quick transfer. If not in January, in June. Recognising a failure is worth more than perpetuating it.