QSS is a HORRIBLE defensive item

So, we have an item that costs 1300 gold, has a 90 second cooldown, and the item it builds into costs 3700 gold. Meanwhile, we also have ghostblade, whose active cooldown is half of what QSS is, and give me movement speed. If someone starts chasing me, I'd rather have MS that this expensive item with it's long @ss cooldown. Additionally, I can go aggressive with it if the opportunity arises. QSS is a sh*tty item compared to the numerous other item actives available to you.