Why is timing and spacing important in animation?
Proper usage of timing and spacing in animation makes way for a  more believable and real character form. At the beginning of this animation sequence the character was quickly picking up both the 20 lb. and 50 lb. weight at the same time. This is unrealistic as if I were to pick up a 20 lb. weight with one arm and a 50 lb. weight with the other I CERTAINLY wouldn't be able to pick up the 50 lb. one as quickly and easily as the 20 lb. weight. It could be questioned if I am in general able to pick up a 20 lb. weight at all.
Animation that violates the laws of physics and basic human anatomy tend to be considered poor and choppy. At best perhaps such an animation would be viewed once on YouTube, by the novice animator's mother out of pity.
What exactly did I do to edit the faulty animation and make it "better"?
 I focused first on the (my) right shoulder of the character, taking the clip of its movement from Key frame number 30 to the end, which would be the Key Frame 50. This allows the right shoulder muscle to appear as though it is moving slower making way for a more lifelike animation.