Why so many people make promises they cannot keep (and do not apologize for breaking their promises)

I believe that if each one of us were a little more sensitive even in one of the ways we relate to each other, our society would be a more habitable place. One example of these ways is making and keeping promises. I cannot help wondering why so many people, including those I know personally, make promises they cannot keep. But what confuses and disappoints me far more is that many of them simply do not apologize for breaking their promises!

I have been extremely careful in making promises. Before I make a promise, I consider all the imaginable conditions, and only after making sure that I will be able to keep it, I make a promise. But I have an impression that many people do not bother too much to ask themselves before making their promises. Do they do so simply in order to please others with their promises that sound pleasant at that moment? I simply cannot understand their mindset, as I prefer disappointing someone by not making a promise unless I am sure that I will be able to keep it.

But of course, there may arise conditions you could not foresee. So it sometimes happens that you are left with no other choice but to break your promise. I think this is understandable and pardonable. But what I can neither understand nor pardon is lack of apology for breaking a promise whatever the reason for it is. In my opinion someone who could not keep his or her words has an obligation to explain why and apologize. I can be rather tolerant of people who cannot keep their words as long as they apologize for this, but I cannot be equally tolerant of those who do not apologize for breaking their promises.

It takes a long time to gain trust of someone else, but it often takes a moment to lose his or her trust instantaniously. Unfortunately, I continue to encounter people who do not share the same view with me about the above mentioned two principles of sensitive interpersonal relationship. But every time I encounter such people and suffer from their misconducts, they remind and convince me that I should be extremely careful so as not to behave as they do, as theirs is one of the best ways to lose trust by many sensitive people, including those whom we considered as our best friends. In my life I have no room for such untrustworthy people.