With zerg it was pretty easy to get used to a rotation of spreading creep, building, and spawning, leaving just enough time to micromanage units which were pure value - assuming the enemy didnt prepare (which everyone did obviously)
thus, that little bit of time that could be used to micromanage units, had to be used wisely to overcome these obsticles
Devote too much time to micromanaging and the macro game fails - devote too heavily to macro, and your units will get 0 value.
With byzantine, there is no time to micro, let alone use the abilities of the units lol