Too many times we do exercises trying to isolate and target certain muscles without fully understanding the implications on the body as a whole. The body is not made up of segments that can be trained in isolation. Our bodies are infinitely intelligent and perform as an entire system. This system strives for balance and symmetry.
The way you move your body, your form in particular, impacts the outcome of all your training. The smallest mis-alignment will unnecessarily stress the wrong muscles and pull tension away from the intended muscles keeping you from achieving your goals. By focusing on moving precisely, your muscles will begin to lengthen and release while awakening those that are underdeveloped.