Saw this comment:

It's a contractual thing, if he plays 90 mins x times Arsenal has to pay add-ons to Lyon and increase his salary. Same happened with Podolski who was always subbed right before the 70th minute. No surprises here, Wenger wants to make profit which is in this case incompatible with the sporting goals of a proper club.
Don't know if it's true. But it adds a third possibility to the sabotage/ mental breakdown list of reasons. I've seen Lacazette's fee expressed as anything from £44mill through £52mill. So I guess there could be £8mill potential profit to add to the last transfer window up for grabs if Wenger can do what he does best, fuck the players and the fans over for personal gain for himself and his leech of a boss.