One of my pet peeves is the use of the word “Professional”. It is the ultimate lever. Or, at least the ultimate big stick. Any given cube-kibbitzer can say “Well, that just doesn’t look professional” and their flatulent comment will somehow be imbued with a kind of transcendent credibility. Other cube-sitters will piously nod their heads in agreement- “We’re concerned that the chair just doesn’t look professional”.
Management or HR can proclaim that your attitude, presentation, or apparel isn’t “professional”. The word professional is a kind of wild card, a Joker in a stack of social cards that can mean anything you want it to mean. It is a kind of peer pressure of the sort that the cool students in high school used to decide who was cool and who wasn’t. It is an upgraded “ugly stick”.
What is amazing is the extent to which it works. It is like a phaser set to stun. It stops people in their tracks. This is why I keep saying that business is part of anthropology.
Lamentations on Chemistry 
My boss frequently gets this thrown at him by the undergrads here. Most people who have been around for a while just shake their heads and sigh. Whenever he shows up in a shirt with a collar, it usually means he’s meeting with someone very important. (We think he’s allergic to ties.) Usually he shows up in a t-shirt from the 80s with lots of holes in it.
Then again, he actually goes into the lab a few times a day. That explains the holes…
A trade professional wields authority by virtue of personal responsibility and suffered liability, plumbers to particle physicists. A Korporate Kulture professional dresses well, worships local rules of engagement, plays a good game of golf, and has an Officially supportive wife.
The former is subject to empirical validation and falsification. The latter collectively exults in technical incompetence exercising intellectual irresponsibility. Personnel straddles both worlds, suffering the burden of accepting the former to keep the latter and itself funded. Personnel splits the difference and only hires drinking buddies. Talk abut single malt scotches, haberdashery, sports… anything but science during an interview. Frat boys despise and fear nerds.