‘STHIR SUKHAM ASANAM  patanjali one of the ancient yogi says  in his yoga sutras that one should always  take the pose is still and gives you relaxation. So in the pose one can breathe and help different body parts. Being compassionate on ones body only than we can be compassionate to others as they are also bodies.  Body has its own language, so it is very important to listen to your body.

Staying in the pose helps to stimulate the glands, strengthen the body,  increase the flexibility, and range of motion of the joints.  

One should always take the asan at their comfort level. It is very important to help the body not to hurt through the poses.