They do. This little fact escapes many who talk about their use. There are many drawbacks to the handling and use of nuclear weapons. They require constant maintenance and testing by highly trained individuals to ensure they are safe. Bear in mind that these are devices, sort of like a car. Lots of complex moving parts, batteries, fuel.
Stick either one in your garage and leave it alone for 3 years, and it probably won't work. Leave it there for a decade, and it definitely won't work.
Thank you for your sanity on this subject.