Spring of last year I went through a 2 week period where I had 6 flats. I had a sheathing screw, roofing nail, wire from a tire belt, a piece of glass twice and a pinch flat. Three of the flats were in one morning. IIRC, I had one more flat, I think in June. I have had zero flats since then, approximately 8,000 miles. Sometimes things just happen. If I am lucky enough to go all of 2021 without a flat, I will give some credit to having mounted new tires on the 4 bikes that I ride the most. My miles are spread among the 4, so all tires are still in good condition.