What is one difference between the Simple Gear Train with Same Size Gears and Simple Gear Train with Different Size Gears?

One difference between a Simple Gear train with Same Size Gears and Simple Gear Train with Different Size Gears is the that the number of rotations of both shafts in the Simple Gear Train with Same Size Gears is the same the number of rotations of both shafts in the simple Gear Train with Different Size Gears are different

Explanation:

A simple gear train is one in which each shaft has only one shaft, and the motion of one shaft in transmitted to the other when the gears are in contact

well cos like a ds it doesn't really die out, unlike for example, fifa, they always come out with a new version, so lets say your fifa 18 is charging you to update the teams and stuff, so, if messi were to go to real madrid (never gonna happen) it would switch messi to the other team, until the owners of fifa come out with fifa 19, then the game would eventually stop updating, and back to the ds, it doesn't really stop working after sometime because there's lots of things that it could be used for, and idk if u know what i'm saying, but long story short, samsung, represents the ds, if they still work, and people love them but not the new version, the old version still works, so they don't really force people to buy new phones, get me?