Masks may be recommended during “cold and flu and COVID-19 season” indefinitely. But guidelines change as situations do. The value of any preventive measure depends on where you are, and where the virus has been surging. Masks are just one of the tools in our kit of interventions. Like any tool, they are not simply good or bad, any more than a bandage or an EpiPen is good or bad. The value of the intervention depends entirely on when and how it’s used. Wearing a life jacket while you’re in a dinghy lost at sea is a great idea. Wearing a life jacket in your living room while watching Pirates of the Caribbean is a less valuable intervention. Likewise, as SARS-CoV-2 grows less ubiquitous, the value of a mask declines in step. As your community gets vaccinated, you can feel more and more comfortable in the knowledge that adding a mask will not add much benefit. The same principle applies to the future. If SARS-CoV-2 surges again in the fall or winter—nationally or in specific states or counties—then the value of masks could rise again. You may end up being asked to wear a mask in one place but not another, even if you’re fully vaccinated. This wouldn’t be a contradiction or a flip-flop; it wouldn’t mean that experts can’t make up their mind and shouldn’t be trusted. It would mean that a sweeping mandate is the most effective mask guideline, in that moment, to beat back a resurgence. I hope that isn’t necessary in many situations, because I’m already extremely used to not wearing a mask. I hope this summer involves a lot more opportunities to leave home without one, to see faces without that constant reminder of this tragic year. But I’m also not about to throw out my stockpile.