Everything in interviews is "par for the course". You're dealing with other humans and their own odd expectations of what is "normal".
Getting interviewed for a sales position adds another layer of absurdities because some people expect sales interviewees to over-sell themselves and be overly diligent in followup, negotiating salaries, etc. I personally don't subscribe to that line of thinking, but know many people who do.
In ANY case, if they made a commitment to you and missed the agreed-upon deadline, you should give them a small grace period (maybe 24 hours) and then followup. This would be true even if you were interviewing to be the backup-tape swapper guy.
Getting interviewed for a sales position adds another layer of absurdities because some people expect sales interviewees to over-sell themselves and be overly diligent in followup, negotiating salaries, etc. I personally don't subscribe to that line of thinking, but know many people who do.
In ANY case, if they made a commitment to you and missed the agreed-upon deadline, you should give them a small grace period (maybe 24 hours) and then followup. This would be true even if you were interviewing to be the backup-tape swapper guy.