To put it simply - bathtub curve [0]. Basically, every component has certain failure rate (probability that an item will fail after certain amount of use, usually hours) profile, which tends to resemble profile of a bathtub. It turns out to be possible to engineer a product in such a way, that combined probabilities form:
a) very steep bathtub profile (critical/expensive components fail one after another)
b) very flat bathtub profile (critical/expensive components have highly differing lifetimes)
Reading other comments, I think it is important to make a distinction between terms "planned obsolescence" and "engineered to fail". My comment was (and the proposed law, as I understand, mostly is) regarding the latter, others commented on specific ways it can be implemented.
Even though these terms are used in various ways, obsolete product is still technically usable (at least to some degree), but is unattractive, malfeatured or expensive to maintain, compared to current competition, often all in conjunction.
a) very steep bathtub profile (critical/expensive components fail one after another)
b) very flat bathtub profile (critical/expensive components have highly differing lifetimes)
c) something in between
Planned obsolence is a
[0]: https://en.wikipedia.org/wiki/Bathtub_curve
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Reading other comments, I think it is important to make a distinction between terms "planned obsolescence" and "engineered to fail". My comment was (and the proposed law, as I understand, mostly is) regarding the latter, others commented on specific ways it can be implemented.
Even though these terms are used in various ways, obsolete product is still technically usable (at least to some degree), but is unattractive, malfeatured or expensive to maintain, compared to current competition, often all in conjunction.