How assignment works
Every assignment is a label underneath, including the ones that look like you picked a screen.
When you assign a playlist, the dialog offers individual screens and labels side by side. They look like two different mechanisms. They are one.
Picking a screen is picking a label
Every screen gets its own label when it is paired, named after the screen. Choosing that screen in the dialog attaches the playlist to that label.
Two consequences worth knowing.
Renaming a screen breaks nothing, because the screen's label takes its name from the screen. Both change together and the assignment holds.
There is also no such thing as a direct screen-to-playlist link. If you are wondering why a playlist is reaching a screen, the answer is always a label, and it is visible on both.
The screen's Playlists tab says which, for every playlist assigned to it. Its Assigned via column reads Directly, Via 3 labels, or Directly and via 2 labels, where "directly" means the screen's own label and All Screens counts as a label. Select it for links to the playlist and to each label involved. The tab is for reading: assignments are changed from the playlist or the label.
All Screens
A built-in label carried by every screen in the workspace, including ones connected later.
You can't add screens to it or remove them, and you can't rename or delete it. You add playlists to it, from the playlist or from its page on Labels.
Useful for something genuinely universal, such as an emergency notice. Worth being careful with for anything else: a playlist on All Screens is a playlist you will forget is there, on screens nobody remembers assigning.
[!NOTE] Older workspaces may still carry a default playlist attached to every screen. New ones do not. If you have one you cannot remove, ask support.
The order things reach a screen
Labels decide whether a playlist reaches a screen. They do not decide when it plays or what order several play in.
When decides itself: scheduling. Order is alphabetical by playlist title, and priority overrides it: when several playlists are eligible.