Re: The odd thing is
Planned Obsolescence is the cause. If a company builds a product that is so good you only need one of them, then their volumes go way down and the cost goes up (paying for the quality.) So if that company designs the product to crap out after a few years they might be able to sell you the replacements too. True for both hardware and software businesses. There is some opportunity to provide more functionality as technology improves, but that value need to be compelling.
The other scenario is that company B comes along with a substitute product at a lower cost (but with much lower lifetime.) Which one will you go for? If you buy on price you'll buy B. If you buy for "lifecycle cost" you'll choose A.
Don't shoot me for this - I'm only the messenger!