So why are the displacement, the average velocity, and the average acceleration useful? Wouldn’t it always be better to deal with the instantaneous quantities if we can?  Even if we ignore situations where we simply don’t know how an object is moving at all points in time, the fact is that there are many situations where the object’s motion is complicated enough that it is in our interest to look for an alternative to the instantaneous position, velocity, and acceleration to describe an object’s motion.  Though our average kinematic quantities clearly don’t contain as much information as we would have if we knew the instantaneous velocity or acceleration at all points in time, there are many questions we could ask where providing the average answer is “good enough” to answer the question.  As we will see as we continue to move through the course, calculating the average value often lets us ignore layers of complication in a problem that make the math required to solve it much more difficult but doesn’t meaningfully change the final answer.