Another goal is to find as much gold as possible. On the higher levels you will find more gold. Your place on the high scores list depends on the amount of the gold you take out from the Dungeons. If you are killed then you loose 10% of your gold (it is kept by the Dungeons' wizard as a fee). If you quit the game (using the Quit command from the Game menu) you get out with all you gold intact, so sometimes it is better to quit.
If you find the Amulet of Yendor, you will be able to go upstair and return from the Dungeons. If you acheve it you will sell all your equipment with great profit and win the game.