"Don't translate this message"
It is because some parts of the messages are reused in another place or hardcoded by the developper as they are. In case of mismatch it brings inconsistencies between what is described and what is coded. Of course a concrete example would have given us more informations about the precisely encountered situation. Names of products (Windows...), applications (Diffusion, Differential...) and similar are not translated to keep the consistency of the documentation.