How your wrists hinge is important, but not as important as making sure you do not force positions. Here is what I mean.
There are arguably four positions. I say arguably because I am not a fan of positions because they can be misleading. If these positions come from momentum, you are doing fine.
How do you get your arms to straighten naturally, without effort? Watch Part 2 to strengthen your understanding of Impact.
Once you have your elbow working correctly, add a shoulder lift. This is the second part to building a solid shoulder rotation.