By default, your charts update whenever any dashboard variable value changes. If instead you’d like to update multiple variables and apply the changes all at once, you can uncheck Auto Apply Variables in your dashboard settings.
When Auto Apply Variables is unchecked, the filter selections won’t be applied to your charts until you click the Apply Filters button on the top right. Once you’re finished updating your dashboard variable values, click this button to apply the variable changes to your charts.
This can be beneficial for dashboard performance because it prevents new chart queries from triggering every time you make a variable change.