I am guessing, but originally there wasn't a defined writing direction, ancient latin texts are left-to-right, right-to-left and boustrophoedic (continuous left

I am guessing, but originally there wasn't a defined writing direction, ancient latin texts are left-to-right, right-to-left and boustrophoedic (continuous left-right-left line). Possibly the letter direction followed the word direction, and when left-right was established so were letters?