In Hi-Lo, winning both the high and the low to take the whole pot.
Winning the high on a board where no low is possible is also a scoop. Example. In a pot where 3 players put in 80 each, half the pot is a profit of 40 and a scoop is a profit of 160, four times as much. Because of this gap, in Hi-Lo you pick hands that can go both ways (the same holds in Stud 8). Heads-up, a high-only hand (such as K-Q-J) has only a 44% share against a three-card low.