There are people who believe you should turn a steak once, others many times. But what you’re really trying to do is cook the meat to about 125 or 130 degrees over a surface that’s 300 or 400 degrees. If you really want to cook it properly, you should cook it slowly, sous vide, at low heat so it won’t overcook, and then use high heat – not for sealing in juices but because that makes it look pretty and taste good.