What is the difference between the laser light projectors with beams that move and beams that don’t move?

Both products project thousands of pin-points of light, but the moving beam laser light projectors have a very subtle moving "firefly" effect while the stationary beam laser projectors have a static "firefly" effect. If there is wind, the “static” stationary beam laser projectors will look like they are moving, but only the moving beam laser light projectors have moving laser beam patterns.