A holding spot for videos you don't want to lose
It's easy to stumble on something worth watching at the worst possible moment -- mid-commute, mid-meeting, about to fall asleep. Saving it to Watch Later means it won't get buried in your history or forgotten entirely.
Keep the list from turning into clutter
A Watch Later list that never gets cleaned up eventually becomes useless -- you stop being able to tell what's actually worth watching. Removing videos as you finish them keeps the list functional instead of just growing forever.
Frequently Asked Questions
Is my Watch Later list visible to other people?
No, it's private by default, so only you can see it.
What happens if a saved video gets deleted or made private?
It disappears from playback in your list -- you won't be able to watch a video that its owner has removed or set to private.