Once, on a mission trip, I had to eat dinner with someone from a different mission team and the person I was paired up with was a middle-aged man from Texas. I mentioned that I went to Texas once to visit my brother, but I didn’t find my visit to Huston to be much different than a trip to downtown Chicago. He got very upset, scolded me about being rude, and stormed off. I guess I did not take into account this man’s radical love for his home state (and maybe a distaste for my home state), and I could not “unring the bell” because I couldn’t just change my opinion about my visit without it being an obvious lie and also because he stormed off and I never encountered him again.
Once you “ring the bell” it’s nearly impossible to take it back without making your apology or change sound non-genuine or fake. I think that’s what makes it difficult–you can try to talk your way out of a situation but people probably won’t believe you because your first remark made a strong impression on the audience.