Well, since we're on the subject of one thing leading to another, that reminds me very much of a fire we had at the hardware store I worked at, which nearly burned the damn place down.
It started at night in the receiving area in the back, which is where we kept a couple plastic buckets for recycling batteries.
One of them had lots of lithium coin cells in it, all untaped.
The security cam caught the fire starting, as two or more cells shorted each other out with enough energy flowing to ignite them. The fire grew and set the bucket on fire, which was at the bottom of a plywood-covered wall, which also caught on fire.
But no alarms went off, because the owner had decided not to install any fire alarms in that part of the building. So the fire grew and grew, setting more and more of the wall on fire, all of this caught on cam.
Which would have eventually burned a lot of the building, if not all of it, if it weren't for the lucky break. That was the fact that there was a large glass jar next to the bucket of batteries. When the fire got hot enough it started scorching the jar, which was sealed. The jar burst, and the noise of it exploding set off a sound alarm. That alarm alerted a security check--not from the fire dep't. but from the local police, who were expecting a burglary. When they saw smoke pouring out from around the roll-up door, they called the FD, who saved our building. (It was pretty well flooded when I came in to work the next day, and the wall was totally scorched.)
Oh, and after that we kept the battery buckets outside in our shed, and were careful to tape each cell before tossing it in.