" Stop motion animation can create a disorienting, and distinctive, staccato effect, because the animated object is perfectly sharp in every frame, since each frame of the animation was actually shot when the object was perfectly still. Real moving objects in similar scenes of the same movie will have motion blur, because they moved while the shutter of the camera was open.
Go motion was designed to prevent this, by moving the animated model slightly during the exposure of each film frame, producing a realistic motion blur. The main difference is that while the frames in stop motion are made up by images of stills taken between the small movements of the object, the frames in go motion are images of the object taken while it is moving.
Go motion today
Go motion was originally planned to be used extensively for the dinosaurs in Jurassic Park, until Steven Spielberg decided to try out the swiftly developing techniques of computer-generated imagery instead.
Today, the mechanical method of achieving motion blur using go motion is rarely used, as it is more complicated, slow, and labor intensive than computer generated effects. However, the motion blurring technique still has potential in real stop motion movies where the puppet's motions are supposed to be somewhat realistic. Motion blurring can now be digitally done as a post production process using special effects software such as After Effects, Boris FX, Combustion, and other similar special effects commercial software. "
Wikipedia