It’s actually Alexa Notifications.
The Dash Button was a way of quickly ordering something that you ran out of. It now can be built into devices with the Dash Replenishment API.
But what I like about Alexa Notifications is when packages arrive. It’s easy to miss but when I see the yellow glowing ring, I know that something is waiting for me and it’s best to bring it inside to keep it safe.
Amazon might be on to something to just provide a light-based notification system. There’s already the Echo Glow — why not build in the ability to notify through color?