He constantly gets it wrong from the start, in regards to both team selection and the tactics/formation. Whether it's long ball or tikki takka, the majority of managers in the premier league all have a definitive plan. You can see what they're trying to do week in week out. Koeman seems to stumble around, trying desperately to find a winning formula. Sometimes he does, but the majority of time he doesn't. Aside from the City game this year, and to a lesser extent United, I don't think he knows how to set us up.
It's nearly October and he doesn't know his best team or how he wants us to play. That's just not good enough having spent £150 million and for where we want to be. He's on the defensive already and attempting to lower our expectations down to the point where we should be happy with 7th, and like the great one once said he wants us as fans to know our role and shut our mouths. No thank you.