I've always preferred to leave my horse in a stall overnight for safety reasons. If something happens to him in the pasture, I wouldn't know until morning. There's less likelihood that he'll get hurt in his stall. Also, in the winter it's much warmer and safer from other animals. However, it's still a matter of personal preference
Overall health of the horse is better being turned out 24 hours a day, with access to shelter. They don't stock up, less chance of developing heaves, more movement is better for joints and the cardiovascular system. Blanket if need be in winter, but let the horse stay out!
I always put my horse in his stall at night. Many horses get sick if they are left outside without shelter. In some climates it is probably okay, but if you live in a place where the weather gets crazy at times, I would keep the horses in the barn at night.
It all depends on the weather and the condition of the turnout field, and the condition of your horse. A healthy young horse can stay out 24-7 with shelter. An older horse may benefit from half as much turnout and being able to come in and relax in a stall.
Keeping your horse in the barn is fine as long as you make sure to turn him out during the day. It's not good for a horse to be cooped up in a stall 24/7. Turning your horse out at night is good too because he is free to roam.
The main decision putting your horse in their stall is the weather. Snow and icing conditions are the best keeping your horse in their stall. Prevents them from falling and causing and injury which can at times be life threating. A warm summer or fall night is perfect for your horse to be outside where they can enjoy the weather.