Explaining the important parts of a fight once doesn't take too much of your time. Then it depends on the kind of people you're queued up with; are they able to listen to the important stuff, adapt and beat the fight, or are they inept and keep failing repeatedly? If they keep failing, then I can't blame you for leaving. If you don't explain the important stuff, though, you shouldn't be surprised that they won't get it right from the start.