I guess I did it wrong. I'll let you all know in a couple years.
Not wrong. Just POR-15 is so expensive for something that fails so often, and when applied according to their fine print with proper degreasing (they make an excellent degreaser, but expensive).
I've got a friend that's really ticked he paid so much and spent his time to do the whole frame of his Yukon, only to have it peel off in less than a year.
Rusts through the paint, creeps under the paint, peels off; not at all like their claims.
I don't want to revisit repairs. The only thing I'll still use POR-15 for is on aluminum parts. When those are out of the sun, so far they usually stay protected and looking great.
As others have success with it, the only thing I can come up with to explain the consistent failure is the winters here have a lot of freeze/thaw, wet, and salt on the roads. Grasping at straws, but unwilling to waste my time using it.