[{quoted}](name=Warlord Rhinark,realm=EUW,application-id=3ErqAdtq,discussion-id=Ve39tvfA,comment-id=0000,timestamp=2019-02-26T09:16:15.331+0000)
If the idea is that the item is supposed to be flexible so you can adapt to certain situations, a 5 minute cooldown would be too crippling.
The idea behind the 5 min CD is risk/reward and to rely on foresight to adapt to potential future situations. If it had a shorter cooldown where you could adapt on the fly, it would be a 100% must-build item for pretty much any ad champ, ranged or otherwise.
For example, your 2 deaths behind your opponent in top. You pick this item and toggle the defensive option before returning to lane to safe farm for a bit.
Or you know a drag fight is coming up. Depending on team comps and the state of things (whos fed and whos behind), you decide you need to soak up damage or deal damage if a teamfight breaks out. That was my thought - to create an item that offered damage or survivability with the drawback of needing to develop good foresight and macro game to use it properly.