I have noticed on two separate occasions that it seemed new games were much much looser when they first hit the floor, then played tighter later on. Initially easier to get bonus rounds, easier to get accumulaters, better base game return, etc. Then it seemed to be harder to win a month or so later.

Which is more likely?

A. I ran hot out the gate over a decent sample size on both games and the numbers regressed to the mean later

Or

B. Since native American casinos aren't held to the same regulation of practices as the legal jurisdictions, they put a brand new game out set to a higher RTP initially, to get the public to like it and feel more comfortable with it, and then lower the RTP later.

I could see the latter possibly being the case, as people remember winning for a long time and will continue to play that game longer with that initial positive experience. Years even. It's easier to win on a looser game, obviously.

I could also see the former being plausible as well. This was over the course of months, not days, and many thousands of spins, but not a huge sample by any means.

I have heard about people saying games get "nerfed", but couldn't it simply be this is what is happening? The casino just cranks down the RTP? Reprogramming and QA to fundamentally change the game would cost a fortune for the manufacturers, I would think.