The default maximum angular velocity permitted for any rigid bodies (default 7). Must be positive.
The angular velocity of rigidbodies is clamped to maxAngularVelocity to avoid numerical instability with fast rotating bodies.
Because this may prevent intentional fast rotations on objects such as wheels, you can override this value per rigidbody using Rigidbody.maxAngularVelocity.
This value is usually changed in Edit->Project Settings->Physics inspector instead of from scripts.