[jarek]

Well sure, but there's an ultimately sustainable business model if your product needs replacing in 30 or 50 years. (Leaving aside the things like marketing claims of a "30 year" or "lifetime" warranties from a company with a 10-year lifespan.) Capital needed for initial production is then the only issue. But there isn't such a model if the product never needs replacing again.

[TeMPOraL]

30-50 years of replacement time is apparently not sustainable, since most of the things we buy have 3-5 years of expected lifetime tops. As for software, the entire tech industry, including its hardware areas, is nowhere near stabilizing yet. Most software has to be replaced after at most 10-15 years, either because of security issues or just because it's no longer supported by hardware. There are exceptions, yes - software written for Windows 95+ is still alive and kicking, but because most software has to interact with other software eventually (even if by exchanging files), it has to keep up. The rise of web and mobile applications has sadly only sped it up.

Maybe one day we'll reach the times when programming is done by "programmer-archaeologists", as described by Vernor Vinge in "A Fire Upon the Deep", whose job is to dig through centuries of legacy code covering just about any conceivable need, to find the snippets they need and glue them together. But right now, software gets obsolete just as fast as physical products.

[jarek]

> 30-50 years of replacement time is apparently not sustainable, since most of the things we buy have 3-5 years of expected lifetime tops.

In practice, yes, most things we buy are designed to fail. But in principle 30 years is possible, if anyone is willing to pay for it. Lots of people aren't, for many reasons including time cost of money, fashion, or just not caring.

> Most software has to be replaced after at most 10-15 years, either because of security issues or just because it's no longer supported by hardware.

Yes, so there's the answer for why the software upgrade treadmill exists: it's for software not important enough to run on dedicated separated hardware. Few people are upgrading CNC controllers or power plant controllers or aeroplane controllers because of security issues or because the hardware is no longer available.

Anyway, even on the consumer side the lifespans are rapidly lengthening. In the 1990s running current software on five-year-old computers or using a five-year-old OS would have been basically unheard of in the mainstream. Today a five-year-old computer is only a step behind current and Windows 7 has turned 6 years old and is still extremely widely used.

[sangnoir]

> n practice, yes, most things we buy are designed to fail. But in principle 30 years is possible, if anyone is willing to pay for it.

My mom is still using a cooking stove she bought in 1982, as a second hand purchase. Parts of it have been repaired/replaced, but I don't think they make em like they used to: I doubt a 2016 stove will make it to 2049.

It's not that creating more durable products is significantly more expensive (it could, and was done in the 80s), its that manufacturers cut costs of manufacturing and their B.o.M. in the interest of maximising profit.