Syncs
A sync is one pass over the Fetch box: browse its listings, match them against your followed shows, download anything new, then refresh Plex if something landed. The Syncs tab is the history of those passes.

Scheduled and manual
Set a schedule in Settings as a cron expression (the * * * * * timing string) and Fetcharr checks the box on that schedule; changing it takes effect without a restart. You can also Sync now for every enabled show at once, or for a single show from the Shows tab.
Reading a sync
Each row shows what the pass did: downloads, failures, deletes, or nothing (empty). A sync is marked ok unless something failed. An incomplete download (a partial recording) counts as a failure rather than a skip, so it stands out at a glance instead of hiding in the noise.
History
Sync history trims itself to the latest 500 rows. Clear individual rows or the whole history from the tab, and filter by activity: DOWNLOADS / FAILS / DELETES / EMPTY.