Anime/manga has many gems and exceptional stories under its belt. More times than not there is more mediocre material than high-quality material, but that will eventually be lost to the sands of time. There are a variety of reasons why mediocrity happens in anime, and here are.
>The Forgotten Protagonists
The quality of the protagonist often is a sign of how good the story will be. It is hard to get emotionally invested if the main character has the personality of a tree stump.
>Predictibility
Often, middle-of-the-road anime uses tropes and plotlines that have been seen before. Despite having unique characteristics to hook viewers, these shows tend not to bring anything unique to the table. Shows being predictable is probably the easiest flaw to notice when a show isn't living up to its promise.
>Shallow Themes
An obvious sign of an exceptional anime is its exploration of thought-provoking themes. However, mediocre shows fail to meet expectations when they cut corners with the other points mentioned. One flaw can easily snowball into many flaws and cuts what good there may have been. The unsatisfactory exploration of ideas introduced in the story can leave viewers feeling unsatisfied.
One anime that left me unsatisfied was Back Arrow. There is a new mecha game called Back Arrow where characters transform into mechas. There was more to the story than I described, but what I described was the only thing that made it stand out. There was no depth to the story, the protagonist was boring, and the story was predictable. Do you remember any anime/manga that did not live up to your expectations?