If you lay a book with the front cover facing up, the top to bottom printing will be right side up.
If you lay the book with the printing bottom to top, the binding print will be right-side up, but, assuming a right handed person grabs the book with their left hand, and turns it as one would so they can open it and turn the pages with their right hand, then its a natural movement - pull the book with the left hand, turn to face you, open and flip through with the right hand...
If you lay a book with the front cover facing up, the top to bottom printing will be right side up.
If you lay the book with the printing bottom to top, the binding print will be right-side up, but, assuming a right handed person grabs the book with their left hand, and turns it as one would so they can open it and turn the pages with their right hand, then its a natural movement - pull the book with the left hand, turn to face you, open and flip through with the right hand...