I agree there are many good reasons to live at home (economy) maybe taking care of one's parents. There is one thing that comes to mind for me and that is if a man has never left his home because all his needs are being met there (with few exceptions). He may very well never leave. I think that would become a concern if you are dating a long time. The man may never suggest living together because he doesn't want the responsibilities it entails. It's way to easy living at home and dating forever. Why would he give up mom's cooking, cleaning and caring for him? In some ways this is having it ALL. That is just one of the reasons that causes a red flag to go up. I'm not saying that applies to everyone but there are people like this.