Why it matters.
It helps keep framing and camera position consistent during long exposures or comparisons.
A closer look.
Stable support reduces camera movement. It is useful when a longer shutter time is needed without blurring stationary parts of the scene.
Use a supported camera to compare two apertures without changing the viewpoint.
Keep in mind.
A tripod does not immobilise the subject. Follow the equipment manual for stabilisation settings on support.