Over the years of playing video slots I've noticed something and it kind of baffles me. We've all seen new slots come in and then seem to vanish over night on a very simple level this makes sense. It's like any new product, if the public doesn't buy it they die a quick death. What baffles me though are the ones that show up in small quantities, seem to pay too well, stick around for 6-12 months then disappear. My first example is from about 15 years ago, it was the original Battleship machine, Aladdin had a few and I think NYNY did too. Every time I played one I could literally play for hours on $20. While the regular wins didn't pay much the achilles heel of the machine was the battleship bonus, it allowed you to play a scaled down version of battleship. Which means that it was somewhat skill/logic based, once you realized this it was pretty straightforward to always complete the bonus. A very recent example is Plants vs Zombies, for about 12 months it seemed like every strip casino had at least 2-4 machines then it just totally disappeared overnight. I never really got into the machine at first but once I did I never had a bad run, no matter where I played. It seemed like something wrong with the machine and it paid out too often. There have been other examples but what intrigues me about all of them is they seem to have had some design flaw that allowed too high of a payback and once the casino's realized this they pulled them. If my impressions are correct I don't get how they could get so far into the process and nobody did enough testing to realize the flaws. Am I crazy or have others seen this too?