The 1-2-2 zone defense is a variation of the more commonly used 2-3 zone.
The main difference is that the 1-2-2 zone defense is a great defense against teams that score a majority of their points from the perimeter, whereas the 2-3 zone provides more inside presence.
This is because, in the 1-2-2- zone, all 5 defenders have a responsibility to guard an area on the perimeter.
This allows quick closeouts and the ability to contest every shot taken from the three-point line.
Therefore, the 1-2-2 zone is often used against teams that have strong guards and three-point shooters but aren’t strong on the inside.