IPhone 6

iPhone does not turn on
iPhone 6 is notorious for being the slimmest iPhone ever made (see Bendgate). This, combined with the softer aluminum alloy used, causes the phone to micro-bend in the pocket, eventually causing components such as the CPU to become dislodged on the motherboard and stop functioning.

This issue had been mitigated in iPhone 6s with a thicker, harder alloy used for the body.