However, in this case, there is no way to truly prove that the longer we play slots, the more skilled we become in the game because, in this case, we are fully aware that slot games are based on luck, and no matter how much we deny it, that fact will not change.
I can't agree with you in this matter buddy. It's true that longer you play it won't garuntee you victory but it ain't entirely waste of your playing. You see the longer you play the more you will learn on gambling. You will find to counter your losses, maximize your profits. If you just play like for fun 20/30 spins only, you will never learn how to play slots, even the psychology behind the playing slots.
If you really played slots, you will find the pattern there in slots, that if you're losing your money in first couple of spins you should not give up or skip it untill you hit your day. Eventually bigger bank roll helps you most. But money management is needed alway. For me the first rules is, whenever you hit the jackpot or a decent profit from slots just exit from it. But if you play more for profit you will eventually lose all you earning.
Slots is not a money maker machines, that will just print you the money. They wants that you play more, spent your most of the day time with slots. Cause you will lose in emotion.
Yesterday I was down to $60 with more than 800 spins. But suddenly I won a free spins which give me a tltal 100$ , and I've covered my all loses with a profit . I'm telling you this from my personal experience. Not all day is your winning day, but it does not means your maximum day will be your losing day.