The independent update feature lets you update elements in a title even when they are live. They are indicated by an icon of a running man. When enabled, variables that are changed or updated will perform an animated update.
Variables with the Independent Update feature disabled will not be editable while a title is live.
Independent variables are also helpful because they will only trigger a render for the variable that has been updated, whereas variables that have the Independent feature turned off will triggers renders of the whole title.