Where has this come from? I keep seeing people say it, but it's total rubbish. Once again, we started our last game with 4 players bought by this manager. We then brought another one later in the game, and would have started another one if Bolasie wasn't injured. People keep saying he needs his own players, but half of them are his players. They might not have been his first choices, but he'll have to get used to that here - just like 90% of managers in the league have to do.
The 'ageing' thing is a joke as well. You can't sign Stekelenburg and Williams, and give new contracts to Barry and Baines, and then moan that your teams too old. If we have an ageing squad a lot of that is on Koeman.
I've said before, I'm not anti-Koeman and I'm happy to give him plenty of time if he shows that he's going to use it well. I see a lot of similarities between this and the way people talked about Martinez though. I think it was clear where things were heading under Martinez about 18 months before we did anything about it, but loads of people insisted we gave him time. Now we have people saying there's no way Koeman can undo the incredible damage done by Martinez but we need to give him 3 years to try - seemingly blissfully unaware that it was giving the last manager time which they believe got us into this mess in the first place.