With so much amazing anime and manga out there, a person can only reasonably expect to watch and read a small percentage of it. Sometimes, you have to choose whether you're going to experience a series as a manga or as an anime. In some cases, the two are equally high quality, and the choice comes down to what's more convenient for you. But there are also a lot of anime you should skip for the manga.
Often, these underwhelming anime could have been great, but they never finished fully adapting the manga's storyline, which means that relying on the anime alone will result in an unsatisfactory viewing experience. This is the case with Btooom!, Deadman Wonderland, Wandering Son, Gangsta, and more. Sometimes, the story not only didn't finish, it also left out tons of interesting information - A Centaur's Life is so much more complex than the anime gives it credit for! Then there are anime like One Piece that are genuinely enjoyable, but are so long that you might be better off reading the manga if you're a new fan who wants to understand the series without taking on what is basically a part time job.
Which of these anime would you skip in favor of the manga?