Everytime i go out into the hills, i carefully pack all my chosen gear into Karrimor drybags.
All the clothing is neatly folded, and given maximum protection from the elements.
Even when that item of clothing is used during the walk, it is never just stuffed back into my sack any old how, its treated with respect, remembering how much the things cost to buy.
All this to most of you, will appear over the top, a bit excessive, but when certain items have cost several hundred quid to buy, respect it, and treat it well.
Manufacturers give their products a certain shelf life, and some walkers complain that their jacket or waterproof trousers only lasted a year or two.
If you abuse your clothing, throw it around, stuff it into your sack with little respect, then do not expect it to last long.
Flimsy Pertex windshirts were never designed to last over thirty years of continual use, but it all depends on how you look after your clothing.
The same could be said about boot care, look after your boots well, and they can certainly last far longer than your average walker.
I value items ive paid good money for, treat them with little respect, and their shelf life will be limited.