most common interview mistakes

(a). Arriving late.
(b). Dressing wrong :  make powerfully positive. Dress right in a conservative suit, subdued colors, little jewelry (but real gold, or silver, or pearls), low heels (polished) and everything clean and neat.
(c). Play zombie : If you are nervous you can't smile and make the eye contact
(d). No smoking, no gum, no drinking.
(e). Research failure : Find out the company's products and services, annual sales, structure and other key information
(f). Can't articulate your own strengths and weaknesses.
(g). Winging the interview : Write out any answers you have difficulty with, and practice until your delivery is smooth (but not slick).
(h). Talk, Talk, Talk.  : interrupting the interviewer and answering to a simple question with a fifteen-minute reply
(i). Failure to connect you to the job offered.
(j). Not asking questions - and asking too many : Use your research to develop a set of questions that will tell you whether this is the job and the company for you.
(k). Bad-mouth anyone : You don't want to look like a complainer.
(l). Asking about compensation and /or benefits too soon.
(m). Failure to ask for the job :  when the interview over, convey your interest in the job and ask what the next step is.