Final Fantasy XIV 1.0 to A Realm Reborn.

Granted, expansions after that were sold, but still, that one update turned the game around and allowed it to turn a multi-million dollar failure into a multi-million dollar success.

Issue with that is I pre-order the game before release based on false information. Gave up playing after 6 months because it sucked. When they finally got it to what they initially promised. It became almost unplayable by the amount of grinding that had to be done to even earn enough to by a freighter. Again gave up playing. So now sits on my shelf part of my collection.

Oh almost forgot when they updated they corrupted my save file so I lost all the progress I made in that 6 months. So that pissed me off as well.

A lot of games have made things better with paid updates/expansions, but NMS really seems to be the only one where the free updates have fixed the game. Hell, there were jokes going around with the last big free update that people wanted to pay them more for all these free updates.