[rondon1]

This is a grey area. It IS rude to setup an interview then cancel at the last minute. It is NOT rude to send a thank you note the next day and say that you will be perusing other opportunities. Anywhere in-between these 2 conditions is going to offend someone.

It may feel good to explain why you have no interest in working in a place where egos are based on coding standards adherence, it is better to maintain professionalism.

[ctdonath]

In a business environment where people's time is measured in dollars per minute, spending hours just to "not be rude" IS rude.

[Evbn]

I would be annoyed if you interviewed with me knowing there was no chance you would take my job.

[csense]

Any competent manager would agree with you; a candidate who knows they're not going to take the job, but comes in for an hours-long interview with several people anyway, is wasting your resources.

But that's not quite what happened here. As I understand the situation, the prospective employee thought he wanted the job when he went into the interview; but, during the interview he learned things about the place he'd be working in, and the people he'd be working with, that made him change his mind.

This is one of the main reasons that interviews are part of the hiring process: So the company and the individual can learn more about each other before a firm commitment is made, and cancel the impending hiring at minimal cost before it's final, if it becomes clear that that would be the better course.