Amiga won't boot from the Hard Drive, asks for a floppy

I have a hard drive, but the Amiga still asks for a Floppy when I boot.
One possible fix is to upgrade to the AmigaOS 3.1 ROM. It contains bug-fixes and also waits longer to boot. Unless you have a real Hard Disk Problem this is the best way to fix the system that won't boot. In the best case scenario, this happens once in awhile. (mine does this occasionally), it is just one of those things  If you have this problem frequently or you have drives that are not seen by the system at all, even on a soft   (CTRL AMIGA AMIGA) reset.  You could have a more serious problem.  

What causes this to happen, did I do something?

It is usually caused by the Amiga attempting to boot from the hard drive before it has fully 'spun up'. This is common with older or large capacity drives. If this happens to you ,once in a while, breathe easy it is common, and not a major reason to worry, nothing you did or really can do to fix it.

How do I know if I have a more serious problem with my hard drive?
Most Amiga hard disk troubles are fairly easy to diagnose, since the Amiga has a very intelligent hard disk controller. AmigaOS has built-in undocumented fixes for the drives.

Want an example of this?  Let's say for some reason, you delete something on your hard drive and switch off the Amiga before the light goes out. When you restart the computer you'll hear the drive clicking away and it will take about 2^X-3^X as long to startup.
What is happening is that the Amiga is taking the time to fix itself... believe it or not!

How can I tell if the problem is with my hard drive or with something else?

To check if the problem is with your Hard drive or something else. Make sure your system is set up properly. Check all cables and make sure the drives are all connected properly. Also, if you have several drives on your system, some pretty wacky things can happen if your power supply doesn't have enough juice to supply all your drives.
Try disconnecting a drive to see if the problems continue. If the problem goes away it is time to upgrade your power supply.

If you still have the same problem you could have a bad HDD, and it is time to replace it.