Rear disc brakes - poor wear pattern?

I have had a couple of rear disk brake conversions over the years in the hope that I will get some decent brakes.

As part of my rebuild I have put on another kit, all parts brand new including disks, calipers, pads and pipework. I have now done 200 miles ON ROAD ONLY and I am seeing this poor wear pattern.

For reference, I also completely changed the front, again with new disks, calipers and pads and the wear pattern on the fronts seems perfect.

Any ideas?

Riccy, not sure I understand? It looks like they are not coming on rather that sticking?

S200KYS wrote: Mine with the same kit I believe?

Do the still ship them with thin (2mm?) spacer shims that slip over the studs behind the disk?

Yes, same kit and does come with the shims. Maybe I am expecting to much?

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If it helps, I have still got the brake balancer valve connected

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I think I might have confused things for you all. That picture of the shiny disk is the front of the car, nice and shiny and wearing evenly.

The inside of the rear (pictured) has shiny on the outer part of the face of the disk and corrosion in the inner part of the face. The outside of the rear (NOT PICTURED) has corrosion on the outside part of the face and shiny on the inside part, ie the opposite pattern.

All parts were brand new 200 miles ago

I will have to pop the wheel off for a better look, particularly at the pads themselves

Trouble is that it has not been off-roaded. Its done 200 miles on the road since a total rebuild with new components, including a new disk brake kit

Suggests to me that the caliper is not I the same plane as the disk. As in the top outer most part of the caliper is slightly more outboard of the axle. Were all the mounting faces of the axle clean and true?