I changed my brake pads and saw something troubling (I have a '96 Honda Accord and have disc brakes on the front end only). First of all, I knew something was wrong because I had last changed my brake pads only less than year ago. But anyways, when I replaced the driver's side pads, they were worn all the way down. BUT, when I looked at the passenger side pads, they looked almost brand new (virtually no wearing down at all)

. And the scary part is that I replaced them both at the same time when I changed them last less than a year ago.
My question is, what could be causing one side to wear down disproportionately (under statement) to the other, seemingly with the driver's side caliper is doing all of the work? I bled the passenger side brakes and there did not seem to be any air in the line that might be causing the caliper not to compress. Any ideas would be appreciated. Thanks.