When studying distributed systems you have to convince yourself that clocks cannot be relied on. It is hard to do so because all the clocks around me are always working just fine.

When this article was posted here earlier I got an idea that maybe wearing a mechanical watch for a while might help.

I bought a cheap mechanical watch. It needs manual winding daily. If you take it off your wrist it gets out of sync with the other clocks or just stops.

Few weeks with that clock convinced me.