If being a player is like using a flashlight, being the GM is like sitting under a 150 watt lamp. Everything is fully illuminated (sometimes too fully), and nothing is hidden from view.

You’re privy to the big picture, whether you created it (homebrewed the world, wrote the adventure) or read the whole thing beforehand, and it all seems clear and obvious to you.

But when the light is that bright, you can’t see the players’ flashlight beam at all — which makes it tough to know which parts they’re interested in, familiar with or missing entirely.