I have a pair of hiking boots from the early 90's. They only saw occasional use before I got them, but the past couple years I've used them extensively for exploring caves and canyons, and sometimes hiking. Between constant soaking in water and mud, spraying off with a hose, and wear against sharp rocks and sandstone, I'm surprised they've lasted as long as they have. The (original) soles are almost completely held on by Freesole now (by far the best adhesive for shoes), and as the leather gets more holes I'm coating it with freesole, too. Sno seal makes them easier to clean but it's ruining the leather by softening it. Waterproofing is pointless with a big canvas panel on the toes and big holes in the sides. I actually like the holes since they pump out water as I walk! The laces are almost completely shredded, so I'll replace those with paracord before the next trip and see how much more life I can get out of the boots. I might need a few more tubes of adhesive.
I have a new pair of hiking boots dedicated for hiking now. If I used those the same way as the old boots, I'm sure I could destroy them in one or two trips. I already had to have the pair replaced under warranty after the heel cup wore through the leather in only 24 miles of backpacking. They don't make them like they used to!