Like many reality or true-life shows that have lengthy runs, they begin very honestly, but over time they start to become crooked. Due to its popularity, favoritism is shown because people think that they will not get caught. They believe that the fans are too hooked onto the show to realize that things that changed and some participants are being offered extra things or ways to get on the show when they never would have been offered anything like that during the first season.
For American Idol, I believe that a lot of it is staged for the show instead of the reality part. It is unfortunate that this has to happen. However, there are many fake TV shows in the world and it is difficult to know if American Idol is the worst.