The chart is based on AP polls so it is a matter of perception rather than facts such as number of wins, championships, etc. Still, the sample size is large enough to be pretty realistic and staying in the top 5 is difficult unless a team 0-1 losses.
As far as "overrated", saying a school finishes lower than they started just means the AP voters got their preseason guesses wrong. A big factor in their guesses is the previous history of the helmet schools so there is some circular reference going on there.