I agree both parties time is valuable and should be respected. I know I'v had times when I'v had to cancel or ask for a bit of extra time. As with 99% of the gents here I have a regular job and it does get in the way sometimes but I try my very best to let you know as soon as I know.
In my real life job theirs a million things that can happen.
#1 is children most of us have them I happen to have a few more than others and two have disabilities.
#2 real work I'm in the medical field my patients have already paid me to care for them (they always come first)
#3 traffic and or getting lost. I'm the worst with directions even with a GPS I can get lost in a paper bag.
Even if these things do happen a kind phone call, text or email are in order by which ever person having the issue.

Believe me I've done my fair share of waiting around and it really "sucks". When my date is on time (give or take 10 min considered on time) it really makes me want to "cum" back for more