Punctuality

I just don’t understand how people in a work environment who constantly refer to being so busy can swan into meetings 5 or 10 minutes late! I would’ve thought that tightening up your time would help i.e. by arriving to a meeting on time, getting it done and completed on time, and back to work. I do actually feel insulted when I have organised my day around something starting at a certain time and I have to sit there for 10 minutes of wasted time waiting for everyone to amble in, then go out again to get coffee … grrrr!