To me, done means: Is there any other major content or features coming. Its not necessarily about support but, with sk=ilksong for isntance, yes the game is released but if you play it today, vs some time in the future once all the dlc is out, you are effectively playing two sepereate games. I like to make sure I play a game only once all of the content that will be in it is released.

Obviously this is imperfect because look at the witcher 3, after more than a decade they announced a new DLC (Which is a tie in to the new game but still)