I've recently started to re-watch them again. None of them are particularly good so I will just rank them by how entertaining they are

1. Apocalypse (An entertaining action film that mostly follows the story of RE3)
2. Afterlife (Fun film with a few nods to the 5th game)
3. Resident Evil
4. Resident Evil Retribution (Weird but overall enjoyable)
5. Extinction (Overall a forgettable film that threw in the tyrant from Resident Evil 1 at the very end)
6. The Final Chapter (A mostly boring conclusion to an absurd film franchise)

Apocalypse was the only film that felt like an adaptation of one of the games.

Apocalypse was the only film that felt like an adaptation of one of the games.

You are correct.

The most recent film ( Welcome to Raccoon City) claimed to be close to the source material but Apocalypse is still the only one to actually achieve it.