Seeing multiple windows at once reminds you that those windows exist and can be interacted with. It's the out of sight, out of mind thing. People like multiple

Seeing multiple windows at once reminds you that those windows exist and can be interacted with. It's the out of sight, out of mind thing. People like multiple windows not because they interact with them or read them simultaneously, but because they remind you of what you are working on and what needs your attention. Single-window workflows work great on tablets and phones, but when you have a large monitor it's not always necessary to scale windows to the full resolution. Most apps are 1-dimensional — your code scrolls vertically, your video timeline track horizontally, and so on.