Parent comment said: "How does one tell how often a bottle was used already?" I don't think one can tell. How I would go about it: calculate the average number

Parent comment said: "How does one tell how often a bottle was used already?" I don't think one can tell. How I would go about it: calculate the average number of reuse by knowing how many bottles my factory has filled and how many new bottles it needed to introduce/throw out for that. I would also sort out bottles only depending on wear and tear. As long as the bottle is good enough, reuse it one more time.