The fourth season is considered by a lot of fans to be the best of the series, but the finale was Game of Thrones bad.
I remember reading in the newspaper that the budget of season 4 was cut in half, and that the season wasn’t going to be so planet-focused. I haven’t re-watched it in a long time, so I don’t remember too many details. I could also be misremembering what I read 20ish years ago.