- Castles filled with treasure rooms, great halls, royal bedrooms and maybe a kitchen, but nowhere for the servants to work.
- Interstellar starships bristling with weapons and hangar bays, but without bathrooms or fuel storage.
- Cities without the necessary buildings for civic infrastructure.
A little thought goes a long way when drawing a convincing map. Think about the things that the people in the area might need, think about why they may have chosen this area in the first place, and what else they might have brought to the area or built over the course of their habitation. What does this tell us about the area?...the people?...the stories that might be told here?
Not every map needs to be immersed in "realism"...as an example, magical towers might transform themselves to accommodate for the needs of their inhabitants. If you deliberately choose not to include something in your map, what does this say about the location? If you accidentally neglect to put something in, and your players pick it up during the course of play, how will you ad lib elements of the story so that this becomes a point of interest rather than a stalling point for the story?