[488643689]

For me the straps were tearing after about 6-7 years (bought it 2009, might be less plastizer used). Became shower watch for some more years. Sometimes you even forget the stopwatch running for month, but the battery still lasts longer then anything else.

[treve]

Now I'm wondering if you turn the stopwatch on, if it stores the time it turned on, or if it maintains the 'elapsed seconds'.

[488643689]

That's a smart thought, I haven't had!

Could be testable by turning the stopwatch on and then change the time. I have no idea how these clocks work; if they have a Unix time style counter as internal reference, then this test won't work. Would need a 36 bit memory to run for 20 years continuous counting; 30 billion times bit flipping on the lowest bit. Probably done differently.