i don't know whats up with them, but they always fail miserably, even some good players couldn't do anything with Arsenal, Ozil was a really good player he helped real madrid a lot, especially with his assists, but came to Arsenal and became an average player, Arsenal need a good coach, and players who can play good with each other, there has to be chemistry between them, and i think a coach can make that happen.
They had a great coach, they had Arsene Wenger who even though at times really had bad years, still had great years as well so I am not sure if that's the case, even a coach like him who would be in hall of fame of managers in history didn't made Arsenal into some long term big name, sure in branding sense it did but that's about it. So I do not doubt that they would be improving with a great manager, but I doubt it would be as much as people assume, give Pep Arsenal for 10 years and he would not be able to turn that team into constantly championship contender, at beast maybe a chance to be top three but that's about it at the very best.
I think it is the front office and the locker room and the staff all that has to leave, the whole team looks like they ruin the chemistry of everyone that comes in, hence why Ozil became not so great as well, because whoever goes there from another place sees the difference of how not so great the atmosphere is there.
