Your whole day is more productive by giving yourself just one thing to consistently do every day. I tested this theory and set up specific hours for positive morning habits. Every morning I woke up and studied French for one hour, and went to the gym for the following hour. After two weeks, it was not only easy to wake up early, but I was looking forward to everyday (even a dreaded Monday). My life was overall more productive.
Now this is an obvious reason, but still crucial to note. Habits give your day structure and purpose. If you have dedicated hours to your day, you are already going to have more structure in your day, and even your life. You may be at a bar at 1am, and plan to rally to stay out another 4 more hours because you have no plans the following day. However, if you have dedicated each morning to running 2 miles, in order to lose weight, you might just be more inclined to call that cab at 1am, or perhaps even earlier. Structure may sound boring and not fun. But having something to look forward to, stimulates our brains, and gives us purpose.
After two weeks, I could not only hold a basic conversation in French, but I was in surprisingly good shape. This I wholeheartedly credit to the habits I set in place for myself. If you are restricted on time, you can even set small habits in place for yourself like flossing, drinking a full water bottle, or even calling your mom everyday. The choice is yours, just make sure it is something that makes you grow, and keeps the endorphins flowing.
You are happy when you are productive, structured, and growing. So set your goals, make your habits, and start living the life you want to live!