Something "engineered to fail" may be cheaper because materials that don't last so long are cheaper. But it's also possible that the material isn't cheaper at

Something "engineered to fail" may be cheaper because materials that don't last so long are cheaper. But it's also possible that the material isn't cheaper at all, but the manufaturer gains because if the part wears out sooner they can sell a replacement sooner. That isn't a case of "consumers prioritize price". For instance, manufacturers have tried to sell printers which refuse to print when there is still quite a bit of ink left in the cartridge. Printers which refuse to let you use all the ink are engineered to fail, but they aren't cheaper than printers that do let you use all the ink. The manufacturer is relying on the fact that obtaining good information is costly; testing printers to rigorously prove this takes resources, and even when it gets discovered, many consumers won't know that the printer is doing this, so they won't use that information in comparing otherwise similar-looking printers.