They all vary zeit. Some are motivated and some are not. Some are simply testing the market. Some times they acknowledge the comps and test the market and after a period of time, decide to adjust. Others figure if they dont get the price they want they will use the property as a rental. Sometimes there are a slew of comps that give a good representation but there is one outlier and they cling to the outlier.
I guess the common thing is that seller psyche is something that moves in a very deliberate manner for most, but not all sellers. As an agent you get used to it. Pushing sellers rarely works, give them the information and making your opinion known is the best you can do. Ultimately the market response to their pricing is the only thing that works, and sometimes even that will not work.