There are lots of reasons that a home will stay on the market too long. Most often, it is price or that the sellers are unwilling to negotiate or cooperate. Sometimes, there is something that turns up on the inspection that is either unrepairable or not cost effective to repair. It may also be that there is something about the home that makes it unsuitable for financing. Sometimes, it is bad luck for the seller and there is a string of unqualified buyers making offers, and having their financing fall through. If there is a home you are interested in, your agent can contact the Sellers agent and find out what the story behind the story is. Often, there is more than just price involved.
If you would like some help, I would be happy to be considered for the position.