We can put some blame on mfg's their methods and bling design (carpet). However, a large percentage of owners didn't (some still don't) have a clue as to what damage water can do over the long period. Many felt "it's a boat FCS, water ain't gonna hurt it". How wrong they were (are) as their boat's value dropped dramatically with rotten floors, stingers and transom's.
I tried (in vane) to explain the water damage concept to my neighbor 2 years ago. He looked at me strange and insinuated that I was full of crap.
Last words we've had. His 5 yr. old bass boat is open to the rain/snow, parked bow down with the trailer jack deep in the dirt and not moved for 2 yrs. Winterizing some do, but proper storage would go a long ways to maintain the value of a wood-framed, foam-filled, boat. There is NO excuse for neglect!
On used boat think:The more and older the neglect, the bigger the project.
My 21yr old P&J: "NO Foam, NO carpet, No Water ....... No Problem." Dry Storage