Essentially, the easier it is to make, the less protection it provides. The Gesture is easy to make, easy to throw out at an eldritch being should they be right behind you, but it will not protect you for very long. They can make you flinch, or make you fight for your life against human targets, and all the power behind that gesture is lost the instant you break it due to instinct, either fight or flight.

The Simple form is easy to draw and easy to place anywhere, giving it versatility. But it nowhere near as strong as the Broad form, especially when the Broad form is set into a stone and carried on your person. But then it is less versatile in where it can be placed.