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Rotation of a planet is dependent on many factors, only one of which is the initial motion attained coming out of a big bang. Take the instance of your Earth, during the passage of her brother, the 12th Planet. Rotation slows and then stops, for days, and then after passage resumes to the same pace as before. This is because of the other factors involved in rotation, which remain in place in your Solar System and have their grip on the Earth.
Rotation is due to a mobility difference between the core of a planet and the surface, and for lack of a better analogy we relate this to a dog chasing its tail. The core of the Earth is liquid, and mobile, and has a mind of its own. As the Earth moves in its orbit around the Sun, the relationship of the core of the Earth to surrounding influences changes. A child standing on a merry-go-round and wishing to face his mother must himself turn a complete circle in order to do this. In like manner, the heavy Core of the Earth moves to face or escape magnetically related forces in the Universe about your Solar System, dragging the surface with it. The core is not homogeneous everywhere and thus parts of it are strongly attracted or repulsed to this part or that of the Universe about it, so motion in the core is constant. No sooner does a part of the core move to the far side of its liquid tomb, then it finds itself presented with its old problem again, and sets into motion once again.
Now as the Earth takes 365 days to orbit the Sun, and rotation happens once a day, it would seem at first glance that the merry-go-round analogy is incorrect. How could rotation started because of the Earth's orbit, a yearly affair, turn into a daily rotation? Motion is not a controlled matter, as anyone riding a bike without brakes is painfully aware. In the liquid core of the Earth, there is little to stop motion, once started, save the desire of parts of the core to approach or escape magnetic influences in the Universe. Rotation starts because of these external influences, and thus is always in the same direction. The rate of rotation is due to the liquidity of the core, as the brakes are never applied. Thus, the parts of the core that are moving away from an influence soon find that they have created their problem again, as the motion of the Earth has placed these parts back where they did not want to be! Round and round, like a dog chasing its tail.