Did you know Sittman and Pitt of Brooklyn, New York develop a gambling machine in 1891[1] that was a precursor to the modern slot machine? It was based on poker and contained a total of 50 card faces. The payout system at that time isn't directly money but rather goods like beer, and cigarettes and is dependent on the establishment offers. It was played by inserting a nickel and pulling a lever which would spin the drums and the cards that they held.
Read more of its history here[1]
[1]
https://en.wikipedia.org/wiki/Slot_machineIt's incredible. I did not think that gambling machines appeared so long ago.
Probably, the inventors of the first slot machines did not think that they were changing the gaming industry. Most likely they just wanted to design something new and interesting.