Each day at 12 am the Minister is ready to perform the Sacrament. It doesn’t really matter what you did or didn’t do the previous day or even the quality of your code: the most important thing is that you attend the stand-up and talk about something.

Bosses, PMs, whatever, have to re-organize their priorities (there are at least 36 different things in a project more important than this meeting).

“Please let us know with at least 34.3 hours’s notice if you can’t attend a stand-up”

It’s not a Sin and the reason doesn’t matter. 

Being flexible about meetings helps generate a good atmosphere in the project, which in turn helps you keep motivated -and this, believe me, is something that the client is interested in.