let the words be alone

Words are abstractions and the cost of abstraction is loss of information. Adding graphics to text may partly compensate for this loss of information, but to say that it is better is misleading. The loss of information may be intended.

In literature, deliberate vagueness enriches the product by giving it a greater number of interpretations. More people end up "seeing" things that they can relate to. In science, deliberate vagueness lies at the very foundations. A certain degree of abstraction is necessary to see the underlying structure, and measurement involves the act of assigning abstract symbols to various phenomena.

Math Example: You can illustrate the notion of a function by drawing a polynomial on the board. But the notion of a function can only be defined abstractly in mathematical symbols. No matter how many examples you give, you can never pin down the concept in images. In fact, students are often misled by the images.

Physics Example: Often low dimensional dynamics can be explained with graphics, but they are only "understood" when the formulation is made in higher dimensions. (Of course, in higher dimensions there can be no graphical illustrations of mathematical arguments.) Proofs often become shorter and more natural at higher levels of generality.