Nuclear launch codes are an example of data that has been committed to a branch that must be removed at all costs. Imagine if one had access to the launch codes for a nuclear warhead, accidentally committed them to a branch and then pushed the branch to a public place.
In real world situations most people do not have access to nuclear launchcodes. Users may have data such as passwords, proprietary code and other sensitive data. Accidental release of this type of data is potentially damaging to the branch owner -- perhaps damaging enough that the developer may hope for a nuclear disaster!
A user dealing with a nuclear launch code problem needs specific data in the branch to be exised at all costs and in a rapid manner.