I feel like Arteta has one season left to prove himself. He either (a) stubbornly buys no attackers again, carries on the way we are and wins nothing of note again (although I don't feel he's the reason we haven't signed a striker given his comments to the media since September about needing attackers but not getting any). Or (b) Berta gets in a load of players in the right position that we need with another big spending summer, yet he still wins nothing and then big questions are asked and the pressure ramps up. It's one thing to win nothing like Wenger did, but also spend little. A board is not going to sanction another summer of £200m+ if nothing ever comes of it. Whichever of those two scenarios happen, the pressure will be so built up that he'll find it hard to stay without winning something next year. Scenario C is we sign a load of players and we win something big.
I predict scenario B is the most likely. We get in Zubimendi, Gyokeres, Gittens and some other randoms and still win nothing. I don't see scenario A being likely given all the talk about players being signed. If we make the signings that are being rumoured (and let's face it, why employ Berta if we're going to have another window of doing nothing), there can't be any chat next year about missing pieces in the squad.