I fixed a problem with a hose I bought last year. It didn't fit the faucet well and leaked, so I wrote it off. (I think I was frustrated with a lot of things at that time, even more than I am now.)
Upon further examination, there was a gasket that should have been at the back of the metal cylinder that contains the threads, but it was at the front, preventing it from screwing all the way onto the faucet (huh, huh). It fit after moving it back.
The protip here is that sometimes you have to look inside the thing that is not working, just a little bit.