When your mid laner forgets to buy before the 1st wave crashes.
Rookie mistake.
Rookie mistake.
Extended BM.
It's a handicap. How nice of him!
Naisu.
Wait, did that actually happen in Worlds?
Game 5.
IG vs KT.
Rookie forgot to buy an item (probably clicked it and it didnt register, or he barely misclicked), just ended up with a ward, and missing half his first wave.