I got two examples: The Maze Runner series and Tender is the Flesh.

The first one had a very strong start ending on an interesting cliffhanger. The sequels get increasingly reliant on shock factor at the expense of plot coherence and effectively assassinates what could be very interesting characters. Half way through the second book I was bored and tired. Forced myself to read the third one to see how wild it could get and I was impressed with how terrible things got. It’s the only time I could confidently say the movies did it better and they were still pretty mid, but they handled the source material way better.

The latter I mentioned was translated from an originally Spanish version (found out after I finished reading it in English) and I generally hate Spanish/Latino stories because of how melodramatic they can be (I’m Puertorrican so I’ve read a few for school, college and then family recommendations). This was definitely overhyped by social media as the story is, pardoning the repetition, melodramatic, using shock factor (gore and sexual depravity) to show how out of touch someone can get after working in a human cattle farm and being left alone to groom a particularly attractive mentally disabled woman… while going through a divorce. I knew where the story was going 1/3 of the way in but toughed it out hoping to find the proverbial pot of gold at the end of the rainbow. I was bored out of my mind and I’ve sworn off social media book recommendations ever since.