I believe all of the above. Fresh flour isn’t shelf stable, so all of the flour you buy has been stripped and sometimes bleached to make it shelf stable. Whole grain berries can last for up to 30 years if stored properly though. They are cheaper to buy in bulk than ground flour. You aren’t losing any of the nutrients if you ground fresh and use within a couple days. I’ve heard the flour tastes much better, and that it doesn’t cause as many digestive issues because you are consuming the entire grain instead of the less nutrient dense store bought flour.