My first thought when I saw âVacuum cleanerâ was that the answer might be âthings that require electricityâ. It felt like a solid, simple starting point. When âAquariumâ popped up, it seemed to fit perfectly. I was confident enough that I almost typed it in, but decided to wait for a third clue. Then âCar engineâ appeared. While many modern engines rely on electrical systems, the core function isnât purely electricalâitâs mechanical and chemical. The theory was already getting a bit wobbly. By the time âDrip coffee makerâ showed up, my initial idea was on life support. While it uses electricity, so do countless other items that werenât on the list. The pattern felt too broad and ultimately meaningless.
The final clue, âEmail software (targeting spam)â, was the one that completely destroyed my electrical theory and forced me to start over. I stopped thinking about power sources and started thinking about function. What does a vacuum do? It pulls dirt out of the air. What does an aquarium do? It keeps water clean. The word âcleanâ and âpurifyâ kept bouncing around in my head. Then it hit me: what component in each of these things performs that cleaning or purifying action? A filter.