Sure, the standard cheap mechanical timer has DOA's and failures because its a cheaply made machanism; but the basic electro-mechanical switch on a clock design has been around since the 70s.
I find the timers are best replaced after say 5-8yr because they're cheap and i dont trust the plastic once it brittles up.If you've been running one over say 50% of its rated load it might be entertaining to crack it open and see how much the conductors have softened.
The key point here is complexity. It's hard to argue mechanical timers are more complex than digital ones: in the sense of number of key components vs their reliability vs their average lifespan.
Good software is simple.
Nothing in the smart home category, as implemented today in retail products, is simple.
I find the timers are best replaced after say 5-8yr because they're cheap and i dont trust the plastic once it brittles up.If you've been running one over say 50% of its rated load it might be entertaining to crack it open and see how much the conductors have softened.