I found some roulette operators are so routined from the number of times they have spun the wheel and lauched the ball over the years that the movement of grabbing the ball, turning back and swinging the wheel, and launching the ball has become so engrained as to actually shift the odds. It is not that you can predict the next number from the previous, but the next quadrant on the wheel given the previois outcome is…
This took place in late 1970s | early 1980s.
It's much simpler with todays tech to do something similar with good camera feed and computer vision (rather than a spotter with clickers watching ball and wheel).