Front brake rotors/pads

I just replaced the front brake pads on my 2002 wagon. At 75000 km, I am not surprised that it needed to be done, but what bugs me is that I also had to replace one of the rotors because there was no pad material remaining on the inside left, just steel rubbing on steel. There was no warning that the brakes were worn out until I heard graunching noises just as the car would came to a halt. By that time, the rotor was too badly gouged up to be machined

Most of my other vehicles have been older GM products, and their front pads have a little steel finger that makes contact with the rotor and squeaks when you still have a sixteenth or so of pad material left. It lets you know audibly and in no uncertain terms that you need to take care of it ASAP.

Seems to me that the lack of a squeaker in the front caliper/pad assembly on my Focus is really crappy design. Is this design omission typical for Fords? Has anyone else had this happen??

Lots of makes and models don't have pad wear sensors. I always check mine when doing an oil change. Did you check the rear brakes?