Anti-Climacus

Man, I remember when Slate's attempts to troll the internet were so much better than this:

Ask yourself: Why is it so vital that I be smoothened? ... You use your crisp clothes to advertise yourself as a rule-follower, and you hope that in turn you will derive benefit from being perceived as one who follows rules. "Oh, he took the time to press his shirt before he showed up for this job interview. So I guess he must be a reliable and trustworthy employee."

Alternatively: ironing your clothes shows attention to seemingly inconsequential detail, and most jobs require attention to be paid to some details whose import is not always obvious. Van Halen's Brown M&Ms were another example, and a pretty good test of what it was supposed to measure.