Many golfers have been taught to keep their left arm straight. Some interpret this to mean a rigid arm that’s almost locked which can restrict your mobility. Do you want a 90-degree angle in the left arm (right-handed golfers)? Of course not, as we need width in the swing. But a soft left arm with a little bit of bend actually increases your leverage and can amp up your power. When I was competing in long drive the left arm softness increased my arc and enabled me to create more speed. Give it a try.