I was performing a brake job on a 2004 Honda Accord. The caliper guide pins were corroded on both sides and the pad wear was uneven. It was so bad, one side needed a new bracket because the guild pin rusted in the bore. No amount of heat or mechanical force could remove it from the bore.
It was obvious on the last couple of brake jobs the technician failed to service the hardware. Now, the guide pins had become so rusted it was preventing the caliper from applying their full force to the calipers.
After the owner drove the car home, he comment that the car had so much more braking force and he felt a lot safer.