2-3 is a zone defense most notably used when looking to slow down the game against a team that is a great driving team. For teams who are outmatched in size or athleticism, 2-3 works best because it forces the team to have to be patient and pick their spots. In man to man, more talented teams can pick you apart, but in 2-3 they have to understand team principles to break the zone. If they’re a poor shooting team, it’ll work even better.
Some negatives of running the 2-3 is you usually give up more offensive rebounds compared to man defense and the opposing team is also in control of the possession time. 2-3 doesn’t usually apply a ton of pressure on the perimeter, so you’re not going to create a ton of turnovers usually and an offense can eat up clock on the high school level against this defense.