Can be hard to discuss without spoilers. I’ve spoilered a more controversial and recent one.
Veronica Mars Season 3: screwed over by the whole college storyline.
Agents of Shield Season 1: screwed over by the timing of Captain America 2 - it’d have been great if it had been a twelve episode story starting in January, with the reveal in March.
The Good Place Season
its harder to name series which didn’t do this... Crazy Ex Girlfriend had a very specific four season timeline, but parts of season two, three and four still dragged.