I'm now repairing/rebuilding the front half of an nearly unused but abandoned & delaminated Prindle 15. The inner skin was no longer attached to the foam, due to standing water inside, and being many years uncovered in the Florida sun. I came to the conclusion that if (waterproof) epoxy had been used inside as a last coat, water would NOT have gone through the inner fiberglass skin to destroy most all of the original polyester resin that held things together for a (long?) while. That skin looked like window screen when I pulled it off, despite someone having tried the polyester injection trick with ~50 holeshots in each panel.

OK- YES- this was someone negligence! But I like simple minded examples. Chrysler was worse than GM or Ford when building rust bucket cars in the 50s and 60s: 3 years later, they were smoking, rust-hole-filled wrecks. So my dad and many other dads would buy a new one!
So- Why am I driving a 19 year old Japanese car now that never rusted, looks and runs like new, and not a Chrysler? Am I brain damaged? OK- I will read my previous paragraph again.