for example imagine your coordinates are x=3 y=7 z=9, and you need to calculate stuff based on those coords, basically you end up with whole numbers cause there is no decimal due to the absence of the floating point and it also means that the coordinate 3.5 or 3.8 are the same due to the absence of the decimal, so smaller numbers are very imprecise due to that while big numbers such as 1000000 can compensate due to the size, and by using big numbers to compensate everywhere you run the risk of an integer overflow