I expect they haven't come back because you torque them properly. I'm not sure about the low end ones, but my Record square taper, Record Pista, Truvative, Race Face and FSA BBs all came with a ring of threadlocker applied to them. Just to be clear, I would never install a BB without grease or measured torque. My main point was that the stuff that comes on them from the factory can set up even in the presence of grease, and grease should indeed always be used. Applying additional Loctite is unnecessary, especially with a new BB.