Enhanced 393 motor output

why is it good to use a screw instead of an axle, I don’t understand. It seems like the screw would just back out.

it looks to me like the standoff is protruding into the motor housing.

I think I know what’s going on here but I will only note that their is proof in the picture that that particular motor was not used in that configuration at the time of the picture.

It could be used to unscrew part of your robot, so it can spring out into a competition position.