Map Design: Why the Magnifying Glass is a Terrible Symbol for Zooming-in
41latitude.com
41latitude.com
They're all simply better than the metaphor. Obviously a physical magnifying glass held over a piece of paper cannot create or remove information, only scale it.
"Zooming in" in software, however, involves a complete replacement. And at every level, the most(/best) set of information is displayed. When zoomed out at, i.e., Miami, the word "Miami" displayed at a readable size covers up nearby towns. When zoomed in a bit, there's more small towns that can be displayed (collectively covering up Miami).
Moreover: this is probably even the right/best thing to do. At a wide zoom, you probably want the big cities as landmarks. Slightly tighter in, one is more likely to be familiar with the area, and want to know the smaller details. Tight enough again, Miami is the only thing left in view, so it is labeled.
This is not broken, or bad in any way.
"Slightly tighter in, one is more likely to be familiar with the area, and want to know the smaller details."
Someone usually consults a map because they aren't familiar with an area. Do you look at a map to find your way home every day from work/school?
The point of zooming-in is to offer a clearer view. How are you doing that if you're removing details? Instead of creating clarity for the user, you're creating chaos.
"When zoomed in a bit, there's more small towns that can be displayed (collectively covering up Miami)."
Except that the average user is more likely to be using the map to reference Miami and not the smaller towns. Larger cities are of greatly more interest to the average user than the small towns surrounding them; this creates a more than reasonable case for continuing to display the larger cities as you zoom-in. Just consider how many people vacation in Miami as opposed to Hialeah, the city that Miami is replaced with as you zoom-in.