u/b0nf1r33

I was playing with a friend yesterday and he E started red buff vs kayn, he got invaded.
But alright those things happen, what im not really sure about is lee sin starting skill in normal clears, Q has 2sec more cooldown in camps, while having 2 instances of damage + execute (also can early smite to increase Q2 damage), while E has 2sec less cd and providing one instance of damage wich is lower than Q, why would you start a buff with E and not Q?