When do you say that a quanitity needs directions to complete its de
scription??

This question appear incomplete

Explanation:

This question appear incomplete because of the absence of options. However, it seeks to differentiate between a scalar and a vector quantity. A scalar quantity is a quantity with just magnitude but no direction (example is mass) while a vector quantity is a quantity with both magnitude and direction. Thus, a quantity needs direction to complete it's description when such quantities is a vector quantity such as weight (which is the downward force/gravity acting on an object with relative mass). The mass is the magnitude while the gravity/downward force is the direction. It would just be a scalar quantity if it had just mass and no downward force (as in direction) acting on it.