Notify subscribers

Left ticked, a new video lands in the subscriptions feed and pushes a notification to everyone with the bell on. Unticked, it goes public with no announcement and neither happens. YouTube provides the switch for bulk uploads and reposts, so publishing twenty archive videos does not alert the same person twenty times, and creators use it on purpose for anything they want live without a fanfare. It also gets missed by accident, since it sits low in the upload flow next to the licensing options. It has to be set before the video goes live, which is why this is the first box to check when a video went public and nobody appeared to know.