A gear stage tops out around ten to one — that ceiling is geometric, which is why almost every machine that needs more stacks stage on stage, adding parts, mass and loss at each one. This is 28:1 through a single rolling interface. The ratio is set by the difference in pin count from one raceway to the other, so a higher reduction doesn't mean another stage.
Every contact you can see is rolling. The pins roll between two precisely shaped raceways and the retainer only guides them — it carries no load.
Count the pins on the input raceway, then the output. The difference between those two counts is the reduction. Nothing meshes, nothing slides, and nothing has to be added to go further.
Animation is a kinematic simulation of the rolling interface. Efficiency figures quoted elsewhere on this site are targets, pending physical validation.