One simple reason, basically you can see in the diplomacy screen if an empire is equivalent or not to yours, however equivalent could mean that he has even 70% more fleet power than yours, so you never know if you can actually declare war or not.
If you have no vision, espionage would be the only way to know what enemy's real power is (also it would be fun).
Let's be honest, you always reload the game once you realize that you fu**ed up
If you have no vision, espionage would be the only way to know what enemy's real power is (also it would be fun).
Let's be honest, you always reload the game once you realize that you fu**ed up