I had this problem a few years back on our 172F.  It uses hard piping from the cabin to the caliper assembly.  Apparently during reassemble after and annual in which the rotors were replaced, the piping got bent and the caliper assembly would not slide back out without binding.  It caused the pads to drag on that side and heat up and and ultimately caused the rotor and pads to seize.  The mechanic was able to straighten piping and it fixed problem.  I have seen modifications made on other 172's where the hard piping ends right below the foot step and they use flexible hydraulic hose to go to the caliper.  I think this was done in response to the same problem.

OK, without second guessing the mechanic,or passing judgment on anybody, here's a scenario, seen many times in my career. When changing the linings, the tech fails to fully seat the brake piston in the bore, simply riveting the pads in place, placing the carriers on the brake, and simply pulling everything into place with the 1/4" AN bolts.(He neglects to ensure free rotation of the wheel/brake disc before taking it off jacks.) This causes the carriers (the metal plates the linings are riveted to) to drag on the disc. They are in a 'bind' and while not really "braking" are generating heat, and if a long taxi can warp the disc, binding it more. Sometimes you notice it, sometimes not. With tricycle gear, you just flat spot a tire, with conventional gear, you're in the weeds. Anytime you put a cleveland style brake back together, new linings or not, make sure there;s some 'play' in the brake cylinder, and the wheel turns freely, after everything's torqued up, including axle nut. Occasionally, new linings require a shim for clearance, between the casting halves.For the same reasons noted above- brake dragging.