Honestly, this could be referring to most open-source projects. I’d imagine many of the popular ones were originally made to solve a problem for themselves and then everyone jumps onboard with that solution.
Linux itself also kinda fits here considering it was meant to just sort of be a small project in the beginning and I doubt Linus ever could have predicted what it became.








For those that want the actual answer:
Tap for spoiler
You turn on the first switch for a minute or two, turn it off, and turn on the second switch. If the bulb is on, it’s obviously the second switch. If the bulb is off and warm, it’s the first switch. If it’s cold, it’s the third switch.