You don’t have infinite energy in a day. You only have a couple of things you can do each day. I like to visualise it as having 10 coins.
Each day you get 10 of them. You can spent all of them. But you only have 10, not 11 and definitely not 12. So you better think hard about what you want to spent them on.
I feel this highlights that there are limits to what we can do in a day and makes it more real. Like scheduling everything in your calendar and giving it a time. Which shows is realistic and what’s not.