A lot of slots do this with alarming regularity, i.e it'll hold your balance unbelievably and not deviate between a certain amount, lulling the player into believing 'Wow, this is gonna be a good session!'.
Then, as if by magic, it'll go on fantastic death plummets whereby the scatters have been seemingly removed, and those wins you'd get- maybe 1 in 3 spins- have all but vanished. Suddenly it's 9 dead spins in succession with the odd 0.5x win thrown in so as not to make it too obvious
It's not natural behaviour, it's too apparent, and Bonanza does this better than any other