Why do my front calipers keep seizing up

Bad calipers, bad brake hoses(very common), moisture content in the brake systems fluid too high, bad master cylinder, bad EBCM.

There's nothing to retract the caliper once it grabs it only relaxes , Before I compress the piston doing brakes I shoot a little penetrating juice under the boot and rarely have to replace them , some will say that 's a big no no but I've done it many times overs the decades . It also has to float freely on it's pins , a detail some people don't bother with or understand .