Having 3 or 4 goathead flats in a row with only two tubes - and yes, that has happened. I am absolutely lousy at patching tubes in the field, and, at times, it is almost impossible to find a goathead embedded in the tire to remove the cause of the flat. Also, often the hole in the tube is so small that, upon removing the tube, without inserting the tube in soap and water - even under pressure- one cannot find the leak.
How do I prepare?
Well, I carry two tubes, a variety of patching material including stick-ons, and mostly a good cell phone with the address book filled with a number of friends who would gladly pick me up. However, my wife and our "sagmobile" would be the first I would call.