AutoFsck improves the disk checking process by checking the disk as the computer shuts down, rather than while the computer is starting up. The developers describe it as so:

"AutoFsck is a script which automates periodic disk checking in such a way that it no longer bothers the user at boot every 30-ish times, and is streamlined in a friendly graphical user interface.

AutoFsck ensures that the automatic disk check will no longer inconvenience you by making your boot times very long.

It's really quite simple, every time you shut down, AutoFsck finds information on your disks. Every linux partition has two important number associated with it, one is the number of times it has been mounted, the other is the number of times it is allowed to before being checked. AutoFsck looks at these, and if your drives are due for checking it asks if you want to check them. If you say yes, your drives are checked before your computer shuts down. If you say no, AutoFsck will ensure that the check will not run next time your computer boots. You will then be prompted again the next time you shut down."
source: https://wiki.ubuntu.com/AutoFsck

This software could greatly alleviate some of the frustration new Ubuntu users face. I believe it is absolutely necessary.