I installed three Toto Drakes in my house a few years ago -- two upstairs and one downstairs. I caulked around the base of the two upstair ones and have had no issues with those. The downstairs one, I just never got around to do the caulking.

Well, that toilet seems to get loose every so often, rocking from side to side. I keep tightening the two base nuts but eventually the rocking comes back. I guess I'm slow to learn, but it finally occurred to me that maybe the caulking, besides keeping water and spills from getting under the toilet and causing floor damage, also serves to hold the toilet in place better than the two base bolts can do by themselves?

Thanks for any help.