The first gen piston only changes from lowest speed to max instantly

FearnatorVG

Step 1 : Boot the game

Step 2 : Play as killer or survivor

Step 3 : In-game, observe generator

Step 4 : Notice the first piston of the generator is only moving at full speed and doesn't change speed the moment it starts moving. When reaching 25% (so the second piston moves, the first piston will move at max speed from slowest)

This is very minor but using pistons as a way to tell how far a gen is, the piston on the first 25% can be extremely helpful if you'd like to kick a generator or not.