I don’t think I can explain it to a 5 yr old…
Simply said, you were wrong. Moving Vertices in Edit Mode doesn’t change the Topology. CG Meshes are ‘made of rubber’ and can be deformed, streched and so on. That doesn’t change the Topology:

Like In Sculpt Mode. Sculpting by default doesn’t change the Topology of a Mesh, only it’s shape.
Unless you activate Dynamic Topology (changes the Topology dynamically), or use a Multiresolution modifier.