I think I stumbled on to a conspiracy.

It is my firm belief that the people that make Christmas lights purposefully make them burn out. I checked 14 strands of lights last year before I put them away and they worked perfectly. Today I plugged them in and only 4 worked. Somehow over the summer something must have "magically" made them go bad. I think they do it on purpose to drive me crazy and to get more money. Darn you Christmas light manufacturers!! Darn you!!!