The saying “First come first served” means that the first aid box does not always have all that you think it has. Someone may have used up the one thing you need. So, when you come to get something that you need out of it, that thing has been used and “Drats!“.
Therefore, I now wish to remind you to check your first aid box that is has all that you may need. Do this at your first convenience. Then pop to the shop to stock up, and not just on plasters, but also indigestion tablets. Trust me when I say, finding only one tablet left at gone past midnight, with a burning heart burn, is no bloody fun!
Still, it’s worked, just the one and I’m fine. Here I am now typing this for you, to remind you to replace what you use, what others use from your first aid box, before your after midnight heartburn or something just as uncomfortable occurs or someone actually needs a plaster.