According to Freaknomics, realtors get about 3% higher average closing prices on their own properties than when they're representing you as a customer. That is the delta when it is their money on the line vs yours.
They start out trying to but then time drags on and they “just want it to be done.” At that point the seller is also prioritizing a deal over maximization.
Agents, since they’ve gone through a tonne of these processes, are more immune to the mental load the sale takes on them. I’d bet they’re less likely to try and blow through those final steps.
You can see this kind of thing play out across industries. In SW, a comparison may be the seasoned dev has no problem ripping apart their candidate solution and rewriting it since that process takes them less effort than the junior.