An interesting question with perhaps not that clear of an answer. Is it from the consumerism "throw-away" culture (bikes, clothing, appliances, etc.)? Is this cultural response ingrained by increasingly short lives of even "durable" goods (I had a very experienced appliance salesman state that most new appliances were made to last 5 years at most....we have all seen Grandma's 50 year old round top single door fridge still working). Low cost has to be made at the expense of quality and durability it seems.There is also the issue of repair costs, the availability of repair professionals, and the hourly cost of such labor with the exorbitant cost of aftermarket parts in many instances. Paying for a compressor and $100/hr labor on that 5 year old fridge makes no sense. Perhaps by design (esp. the cost of repair parts)? Repair parts for bikes are quite reasonable, but again labor is expensive by necessity (the operational costs for the shop and a decent skilled labor pay). Thus.....the bikes end up in the garbage. I recently rescued a mid quality Mongoose alloy mountain bike. Typical Wallyworld assembly job (every adjustment/assembly was drastically off....wouldn't shift or stop. One wheel bearing loose....the other tight). Was apparently dumped and rear derailleur bent....so in the garbage it went. I put an hour and a few dollars into it and gave it to a friend's daughter to ride. I see this constantly....I think "planned obsolescence" is less of a factor really. Cheaply made bikes CAN run a long time with maintenance and repair.