because they have emotional attachment to their property. They are very reluctant to reduce price. The buyers won't buy them if they don't get a good bargain. There comes a stalemate. Sellers are in the worst shape if they happen to live near a new home construction site where builders are having lots of "quick delivery" sales or worse, auction sales. In this case, nobody will consider a used home. Sellers of a used home can noway out perform a builder. Builder can sometimes offer 50% discount if they are desparate enough. But an individual sellers can't afford to do that. Their banks don't allow them to.

Sigh, I feel bad about individual home sellers.