There IS slot strategy. It is called advantage playing. Much like counting cards in blackjack, there is strategy for slot machines. For example:
-casino mistakes (machine set incorrectly)
-excess play funded jackpots moved around due to machines being added or removed which results in an abnormally large jackpot that is still as difficult/easy to hit as it was before but now represents a much larger $ figure.
-most commonly, machines that are designed with scenarios that enable savvy players to utilize them and win.
For example, in the first 30 seconds of this video (https://www.youtube.com/watch?v=G2roTze21Ig&t=6s) there is an example of a slot which was spun previously by a not savvy player, which generated guaranteed win situations for the following spin allowing the player to automatically win on that series of spins. These machines appear in different varieties but the point is, if you actually understand the slot you are playing, you can understand that some slots are designed in a way to be periodically beatable. While this doesn’t represent all slots, it absolutely represents some, and myself and many others make a living hunting these machines.