Just think a while ! Why your left hand is not functional equally with right hand? You know the answer . It is because you don’t use it much. Imagine what happens if you don’t use other organs/limbs of body? It will not will not work with full efficiency. Finally, makes the man sick.
A few people don’t realise the importance of working with left hand .It stimulates the rightside of the brain. If you don’t do it, simply you over burden the left side of brain.
have seen a few officers, rich people don’t hold their belongings. The president of United states also holds his own umbrella. Thus, Indian officers forces their hands to be weak. That hand shows reluctance to endorse.

Also , out of richness, some people burdens the some organs/limbs and causes harm to themselves.
Excessive use of Suger,Computer games ,Air conditions makes the people inactive. Optimum rest and sleep also plays vital role in being active.