A few weeks ago I had a long discussion with
In the context of interviewing, a suit is typically worn. At the time, I disliked the idea that a candidate would be at all judged on their appearance as opposed to their merits and skills.
I’ve decided that wearing a suit to an interview is not about showing respect to the job or the interviewer; it’s about conforming to the tradition of wearing suits to interviews. That tradition has no direct bearing on one’s qualifications for the position, but most companies like people who follow the rules and conform to company policy. Following the tradition of getting dressed up for an interview is an indicator that you are a generally conformist candidate.
Also, in technical fields, it clearly marks a visitor to the building because they’re overdressed.