That is correct, the smallest imperfection, even one you cannot see, can cause a perfectly good, or brand new seal to leak, that is why the seal surface is just as important as a bearing surface when it comes to longevity.
When I had to change the shaft seals on my car at 130,000, I installed new axles also, eventhough the factory units were still tight at the cv joints, but I did not trust the seal surface. I HATE DOIN THINGS TWICE!!