If you want to visualize the initialized solution, you will need to initialize manually. Do this by clicking on the
(Initialize Solution) button in the toolbar or by using the Solution > Initialize Solution menu item.

If the solution has already been initialized (manually or automatically), then this action will have no effect, but it will have no ill effect either. So executing this action after one or more iterations will not re-initialize the solution data. Whatever values had been calculated for the solution variables to that point will be untouched.
If you then change or add models to the simulation, an initialization will set the solution variables for the changed models.