Even the medieval T-O map let you know that you could get to Africa from Europe by crossing the mediterranean. Star maps help you figure out which constellations you could draw or where you could look in the night sky.
If you can’t figure out possible (and unallowable moves) from a map, it’s not doing its job. Many ‘competitive’ landscapes fail on this front.
A good map makes you aware of the tradeoffs between different possible moves. Google Maps also helps you figure out possibilities by showing alternate possibilities and making you aware of the time and distance between those possibilities. The parameters of these tradeoffs vary drastically between maps - on a hiking map, elevation is important while on a driving map it is almost irrelevant. On a research map, cost is important while on a star map the concept of cost doesn’t even make sense.
The Map is not the Territory - a good map will capture the information that you need to make decisions and exclude information that is distracted.
Roadmaps (§Program Design) explicitly point out those possibilities in an opinionated way. The difference between a map and a roadmap is the difference between google maps and the directions the map gives you to a location.
(Wardley)