People cannot put much time into the game because there is enough content to invest in. The classes are almost the same and yes I played all three deleted and did it again for fun trying to 'create' content because Bungie can't do that themselves. Raids don't allow randoms to be thrown together so I never got to do the Taken King content. I got to the Taken King but never finished because one guy kept screwing up griefing the entire party (intentional I have no idea he had connection issues and we found later he tends to grief people on the King desperately looking for one more.)