It’s the outside that matters.
See the outline of the Ankylosaur above, this is an example of an outline. It only shows the most basic of the external features, and nothing about the inside. It expresses only shape and gives a basic idea of what the dinosaur is but doesn’t give us an idea about any other features.
Very similarly, the electron dot diagram consists of the symbol of the atom and the valence electrons. The diagram provides you with an outline and only the external electrons used in bonding. It provides you with information used for bonding but that is it.
What is the electron dot diagram for H?
What is the electron dot diagram for Ar?
What is the electron dot diagram for W?