Yes, I never understood that.
"We can't have him going into his last year so we have to push him out".
Why? It's not a player worth tens of millions walking on a free, it's a manager. The value of a good manager is much higher than a year's worth of comp.
We could have let Koeman continue to build for a year whilst concentrating on succession planning. I doubt anyone believes Ron would have half-arsed dialled it in for a year as he clearly wanted to continue in management.