Caulking – Understanding Why Caulking Turns Yellow

I have seen this happen just once before - a caulk that never seemed to cure. It just stayed runny, even when given multiple days to do so at room temperature. My guess is the caulk was old or stored under conditions that caused it to fail to cure, or perhaps it was simply a bad batch from the manufacturer. Regardless of the reason, clean it out, and redo the caulking job.

You don't have a caulking problem, you have a structural one. The walls and floor shouldn't be moving so much that caulk cracks. And caulk isn't an adhesive for holding up the soap dish or towel bar. Finally, a rocking toilet indicates the floor either wasn't properly leveled or that it's not structurally sound. If these are the issues you are noticing, then you can be sure that there are a lot more serious problems you aren't seeing.

You don't want that contractor back in your house to fix these problems. You want to sue them for gross negligence and to get someone that knows what they are doing to come in and fix it. To fix it right likely requires gutting your bathroom all over again and starting over from scratch.