Apologies: follow through builds trust, not just the words.
In other words, apologies are hollow until they are filled with behavior change.
I cannot tell you how many people express frustration with repeated apologies that are not followed up with consistent behavior change; not just short-term change, but consistent, long-term change. And it is a valid complaint! When somebody accepts responsibility for their behavior mistakes, we begin to feel better that we have been heard and taken seriously, and we can forgive and move on. But when the mistake continues to be made, even if it follows short-term change, it becomes more difficult to forgive, and as time goes on, more difficult to believe that the behavior will actually change. Then the resentment festers, the frustration mounts, and it can feel pointless to continue to address the issue.
In a nutshell, it is one thing to absorb information . . . but that is not learning. Learning is characterized by the translation of the information into behavior change. An apology is a commitment to change behavior. Following through builds trust; not following through destroys trust.