The ability to predict the weather over the next few days or weeks was the principal practical application. Knowing that the rains often begin in two months will be very helpful to a farmer or even a hunter, for example. It's also crucial to understand that the winter days will start to grow longer and that the temperature will drop quicker. If you can count through the year, you can determine that.
Additionally, if you travel frequently, understanding the constellations is a surefire method to stay on course.
Additionally, in order to maintain contact with it, people will just want to comprehend it and worship it or the entity that created it.