I believe the general principle is that at any one time an object can
be in only one place, therefore when you locate an object it can have
no speed because it is where it is. Speed is simply determined by how
long it takes an object to get from one place to another, so finding
several locations for an item is sufficient. The physics of this come
into play when we want to know how fast something is going when we
only get one look... It's hard to spot let alone time an object going
past us at the speed of light.
-JR