Some businesses use Point of Sale Systems that allow for loyalty sign-ups directly from the POS. If a business wants to view statistics around these signups, they will not show up on the circle graph from the main Dashboard (landing page).
However, they will show up on any sign up data exported from Reports>Data Export>Guest Data as long as the "sign up channel" field is selected. This field needs to be selected while exporting data.
Dashboard:
Data Export from Analytics: