Not sure about the machines on the ship but most of the machines in Atlantic City the reels stop spining sooner if you hit the button. This is a built in feature for those who (wrongly ) think that they can control the out come of the spin by stopping the reels at a particular point instead of letting them spin for their preset time. Approx 3-5 sec.
Slot players should take the time to understand the technology behind these machines. When the machine is played a random outcome generator chip instanly determines the outcome of that play and the sends a signal to the reels to stop at the appropriate place to show the outcome.
And Yes they are designed to show you a winning combo on the line above or below the pay line, just to make you think you were sooo close.
Despite what people think it makes absolutely no difference to the computer chip what any of the previous plays were or how long it has been since the last big hit. Every single play has exactly the same odds ie: 1 in 9 chance of even money , 1 in 35 chance of hitting 10x your bet, 1 in 603 chance of hitting 100x your bet ect......
So moving from machine to machine, playing the same machine, jumping on a machine just after someone gets up who's been losing, pulling the handle, pushing the button, playing credits or putting you coins in by hand have no impact on the outcome of that play.
So I know the odds are bad but I love to play them anyway. Silly huh
My 4cents worth, Eric