What do you consider 'beating the game"?

Do you go for the 100% everytime or do you say the final boss is enough? Is there a point in some games where it feels finished to you? I finished the first two donkey Kongs at 100 but am content with saying I beat the third one at 55 or so. Does the game end with the final boss or do you need full completion?

Do you go for the 100% everytime or do you say the final boss is enough? Is there a point in some games where it feels finished to you? I finished the first two donkey Kongs at 100 but am content with saying I beat the third one at 55 or so. Does the game end with the final boss or do you need full completion?