The good thing with my current bike is that it never runs out of fuel, by design. I can pick it up anytime and it just works, it was so 10 years ago when I acquired it, and it'll be so 10 years down the road.

I have a Garmin Forerunner 735XT watch and it needs charging every 15 days, which is better than any "true" smartwatch out there. At some point in the distant-but-not-so-much future the battery will flat out die and there will be no replacement part. The experience from my mechanical watch is entirely different: it keeps on ticking as I move around, and the thing will probably end up surviving me.

Going from zero to non-zero - whatever the value of non-zero is - is non-negligible mental weight. Zero is a freeing experience.

I've had a couple of Di2 batteries fail. One of them went suddenly and I had to grab a train to get home. The other one lost capacity quite quickly, so I'd have to charge it once a week until it got so bad I needed to charge it fully each day until I swapped in a new one.