Interviewing is a multi-sensory experience. And if you inadvertently assault any one of the interviewer's five senses – sight, hearing, taste, touch, or smell – you could blow the interview before it ever starts.
Do not let your interviewer see:
You looking at your watch,
You looking at your Blackberry,
Your numerous unconventional piercings,
Your extensive body art gallery,
Your bare arms (guys, please no short-sleeve shirts with a tie)
Your excessive bling, or
The label on the sleeve of your new suit.
That label? Cut it off, along with the threads on the pockets and the back flap.