Season 1 was a decent adaptation of the books with some cool action scences and reasonable character building. I really enjoyed it and was hopeful for S2.

Unfortunately Season 2 is an absolute sham. The writers have strayed far from the source material and made up various sub-plots that are conviluted and ruin the nature of the characters. It feels like some sort of bad fan fiction. Despite this I quite liked the step up in visuals and thought the actors did the best they could given the terrible script.

Edit: I've just finished watching Season 3 and the story follows the source material much more closely which I like. There are some really cool moments from the books depicted on screen. Despite this, the script is still cringy and a lot the character building suffers as a result. Slightly better than Season 2, but not by much.