AFAIU, one case that subtly falls in this category is when you use ThePackage in two different environments.
The first time, ThePackage is pre-compiled for the set of dependencies specified in the first environment. If you subsequently use the same package in a second environment where some of the dependencies have changed version for some reason (possibly related to an other, entirely separate package that happens to have dependencies in common), then ThePackage has to be recompiled for this different set of dependencies.