Under most circumstances elements are static, and when an element is placed in a design, its position is defined simply by the design plane coordinates on which it lies. It retains that position in the design plane until you move it with an element manipulation tool.
One exception to this rule is association, in which an element's position in the design plane is defined in relation to another element. When that other element is moved, the associated element moves with it. For example, dimension elements can be associated with the elements whose dimensions they display. These dimensions update when the dimensions of the elements, with which they are associated, change.