The 2 recurring themes are: How can you convince anyone of your product if you cant even convince 1 other person to join you? and 1 person just can't do it alone, you need multiple perspectives to dissect a problem.
There are very very very few exceptions, probably enough to count them all on your fingers. That said, I'm in the same boat as you and looking for a cofounder but I'd say don't just go and pick up any cofounder. Take your time because this relationship is something that takes a lot to build and is not like just hiring someone to help you with a task.