If you’re asking, “Why don’t I see updates when syncing?” If the style is not saved, then users of the design system cannot reuse the style. For example, if the one-off change is set on a symbol, when a user of the DSM managed library uses the symbol via the Sketch Insert option, they'll get the symbol with its "official" style, not the unsaved one.
After a layer or text style has been created, it’s possible for that style to become unsaved. This essentially means that an update has been made to a one-off use case of that layer or text style without updating the source layer style (e.g., changing the opacity, updating the hex value from one blue to another, changed the font weight or letter spacing, etc.).
Any time you see a layer or text style in the Appearance panel that is italicized with an asterisk, it is unsaved.
There are two main options when a style is unsaved:
Create a new layer or text style.Select this option if the change you made to the style is new and will now be reused apart from the original saved style.
Update the layer or text style.This option will replace the saved style with the changes that have been made in this one-off use case. Note that if you choose to update the existing style, it will replace all existing use-cases in your document of this style with the new version you’ve created.