This is roughly the current style. You use it because it is. You practice it. You study the market, not what is selling now, but what the publishers are buying for publication in two year's time. Then you write a story that has that special something that will catch the eye of an agent or publisher. Even this might not get you published. But if you are serious about getting published you do it. That does not stop you working on your 30 plus POV, risk taking novel in your spare time.