It’s not just pressing Alt+Tab that’s a problem — pressing the Windows key may do the same thing, as it takes you out of the game and back to the Windows desktop. This isn’t a problem when you play a game in windowed mode, where you can Alt+Tab easily. But full-screen mode seems to be different — full-screen games can’t be Alt+Tabbed out of as easily.

The real question here is why games run in this full-screen mode in the first place, if the full-screen mode itself is a problem.

When a game runs in full-screen mode, it can gain exclusive access to your graphics hardware — this is known as running in “Exclusive Mode.” Windows won’t render your desktop in the background, which saves on hardware resources. This means you can squeeze the most gaming performance out of your graphics hardware by running the game in full-screen mode, and that’s why games run in full-screen mode by default.

Windows doesn’t just have to switch from one window to another when you press Alt+Tab. It has to minimize the game and start rendering the desktop again. When you switch back to the game, the game has to restore itself and take control away from Windows. For a variety of reasons — especially problems with the way some games are coded — the game may encounter a problem while doing this.

You can see this in action when you have a game running in full-screen, exclusive mode. If you Alt+Tab out of it, you can hover over the game’s taskbar icon or press Alt+Tab again. You won’t see a preview of the game’s display area like you would for other windows. The game running in full-screen exclusive mode doesn’t redirect its output through the desktop’s display manager, so the desktop display manager can’t display a preview.