Here's a visual representation so you understand better what I'm talking about. The first picture show the witness mark of where the original seal was riding on the inner retainer. The second picture shows the witness mark of where the new seal design was riding on the retainer. The person who did the replacement obviously just replaced the seal and didn't reposition the retainer. As you can see, the seal lip rides very close to the bevel which is not good. Ideally, you want to be riding somewhere near the middle of the 10mm polished surface of the retainer to allow for axle movement without compromising the seal.

I took this retainer off a guys rig that had a leaking axle seal. The previous owner or mechanic thought it was a simple fix of pulling the axle, replacing the seal and bolting it back up. People who do this end up with another leak much sooner than they'd hope and are confused and frustrated why the fix didn't work.

Here's some reasons why DIYers and Shops fail at this repair:

1) They're ignorant to the fact Toyota redesigned the seal
2) They didn't address the cause of the axle seal failure (clogged breather or worn out axle bearing)
3) They didn't press the parts on correctly, mainly the inner retainer
4) They didn't confirm they had a good mating of the seal and inner retainer by doing the very simple grease test.