Just because you disrespect your time, does not give to the right to disrespect others.
If you are in the habit of turning up late, canceling last minute, running long, you should take a moment to consider the impact you have on others.
The message it sends, the knock on affects, the real cost. Most importantly, it shows how little you care about those around you.
I know you are busy, it is not an excuse.
If you are in a leadership position or behaving like that with customers or partners, then shame on you.
It’s not good enough, do better.