eli5: If modern computers and smartphones etc have no moving parts, then what causes their performance to steadily deteriorate as they age?

Question

eli5: If modern computers and smartphones etc have no moving parts, then what causes their performance to steadily deteriorate as they age?

In: Technology

Answer 1

Lots in here about software but not much about the degradation of electronic components.

Just because they don’t move, doesn’t mean they don’t wear down