The scientific understanding is that Earth's tectonic plates do not stop moving entirely, but their movements occur at varying rates and can change over geological time scales. The motion of tectonic plates is driven by the process known as plate tectonics, which is primarily caused by the convective movements of the Earth's mantle beneath the lithosphere.
The Earth's lithosphere is divided into several large and numerous smaller tectonic plates. These plates are constantly moving, albeit very slowly, due to the convective currents in the underlying asthenosphere. These currents arise from the transfer of heat from the Earth's interior to the surface.
There are three primary types of plate boundaries: divergent boundaries, where plates move apart; convergent boundaries, where plates collide; and transform boundaries, where plates slide past each other. At these boundaries, various geological phenomena occur, such as the creation of new crust, subduction of one plate beneath another, or the formation of mountain ranges.
The motion of tectonic plates can be influenced by a variety of factors, including the distribution of heat within the Earth, the density of the lithosphere, and the presence of geological features such as mid-ocean ridges or subduction zones.
To summarize, the movement of Earth's tectonic plates is an ongoing process driven by the convective currents in the mantle. While the rates and directions of plate movements can change over time, the motion itself does not come to a complete stop.