Yes, ideally, you do. Everyone does. Using your examples above, you know when your boundaries have changed because you live in your skin. I don't live in your skin, so I only know your boundaries secondhand, and I don't about any changes to them unless you tell me, or if I test them and find them different than I did before.

If I find someone's boundaries have changed, I tread carefully while finding out how and why the changes took place, because I want to be respectful of the person in question. It's not for me to go charging through anyone's boundaries because I'm displeased at finding them there. This is easier said than done, especially when I'm frustrated, but I do try.