Why are climbing shoes bent?

Bent climbing shoes are called aggressive climbing shoes. They are bent, and many times also have a curve in the direction of your big toe, to give you more power when standing with your toes on small edges, and to give you more pulling power with your toes. Imagine a piece of paper on the floor in front of you, put the tips of your toes on it and pull it towards you - aggressive climbing shoes make it easier to pull your body weight like this on climbing holds, they allow you to pull yourself closer to the wall and keep you there.

The bend helps you engage more and put more force onto the tip of your shoes, allowing you to add more tension and be more stable on tiny edges that otherwise could be very difficult to stand on.

Aggressive climbing shoes are also great for overhanging climbing, since the added tension and force you can exert with your toes can help you keep your feet on the wall, which prevents you from cutting loose and hanging from your hands, which can be very tiring and costly and could cost you finishing the route.