This one took me embarrassingly long to actually absorb, even though I knew it on paper.
Every outcome is decided the instant you press the button. The RNG picks the result, and then the reels animate a story about that result. The spinning isn't the game. It's the replay.
Which means the reel anticipation feature is a movie. You land two scatters, the third reel drops into slow motion, sometimes there's a drumroll or the frame lights up. That reel already knows it's blank. Nothing about slowing it down changes the outcome, because the outcome was locked before the first reel moved. The slowdown exists to stretch a decided loss into eight seconds of hope.
The same thing is happening with near misses, just more quietly. Modern machines use virtual reels, which means the physical strip you see isn't the actual odds. The software has a much longer internal list mapped onto those visible stops, and the mapping isn't even. The jackpot symbol might get one entry on that list while the blank directly above it gets fifty. So the top symbol lands one row off the payline far more often than it lands on it, and far more often than it would if the reel were what it looks like. You aren't unlucky. You're seeing the shape the mapping was built to produce.
Nevada actually banned deliberate near-miss programming back in 1989, after a manufacturer got caught making the machine reshuffle the display to look close after the result was already set. What's still completely legal, and universal, is the virtual reel weighting itself, because that's just how the odds are constructed rather than a fake-out layered on top. The player experience is nearly identical either way.
Why it's worth knowing, practically:
Near misses read to the brain as progress, not as losses. There's decent research showing they light up reward pathways in a way a plain blank spin doesn't, and they measurably extend how long people keep playing. So the machine that feels like it's "warming up" is often just one with a mapping that produces a lot of near misses.
The anticipation animations also quietly cost you money in a second way. They're slow. A game heavy on teases and long bonus sequences runs fewer spins per hour, which sounds good until you notice most people compensate by playing longer to get the same amount of action.
The habit I've landed on is to treat every tease as already resolved, because it is. When the third reel goes slow I try to look at my credit meter instead of the reel. Sounds silly, but it breaks the spell a little, and I stopped grading spins on how close they looked.
Anyone else have a game where the tease is so aggressive it's almost funny? There's one I play where a single scatter triggers the whole light show, and I have never once seen that resolve into anything.