There have been a few workouts I got rid of, then later reacquired (like CTX and Kickmax). I agree that sometimes giving a workout more of a chance is worth it (though some workouts I know right away I don't like or won't ever do). Three times seems like a good number. (And if you can't bring yourself to ever get around to those three times, that's a good indication that it should go to Ebay!