Working with symbols in Flash also gives you the option to make adjustments to the various color settings of those symbols, on a scale that affects all parts of the selected instance of a symbol without having to permanently edit the original symbol itself. It may be that you dont want this change to reflect in the original symbol, or youre making duplicates of a single object in various shades, or youre animating something changing color but cant leave it as raw lines and fills for various reasons. Thats where the Color dropdown, which appears in the Properties pane when a symbol is selected, becomes useful.