When you compare Spearman and Archer, you compare two units moving at the same speed, furtheremore the archer can not retreat after the attack, so their come the spearman. Also both units are available in the same time.Pentium said:Just like infantry and tanks, or spearman and archers. The same principle for the whole game.
Tanks will be available much later than Infantry (about 8 techs later), also Tanks are moving just twice as fast as Infantry (inside enemy territory), who can aford to loose the speed for the confort of a better defense?
If I am building fast units, it is because I need to move fast, otherwise I will build Infantry and Artillery, that could be used either for defense or attack.