Dear Peanut paying companies (TCS especially), don’t you have some basic manner in valuing the precious time of Candidates? When you’re scheduling interviews, you asked about the current salary and expectation. Even though knowing the peanut you’re going to offer is way below Candidate’s current salary, why are you still processing for further interviews? Don’t you ashamed of yourself calling as a Recruiter? These are basic manners/commonsense, which you guys are unaware of!!!
Talk about compensation or what their billable requirement is. I think it shows that you are putting the cart before the horse because they haven't even made an offer yet, and it also implies that you might be interested for the wrong reasons (if you are more concerned with substance of the work and cultural fit you are likely to stay around longer).
Forgetting the names of the people interviewing you or the firm.
Sounding noncommittal or indecisive in a way that makes you a flight risk. For example, when I ask why you want to be in my market, saying you don’t really care where you end up and you’d try anything for a little while. To me, that signals you’ll be here maybe 2-3 years before moving elsewhere.
Not asking any questions. Even if all your questions are answered, you should still ask each interviewer a question related to themselves or the position.
You should come in with questions from the research you have done already. Don't speak negatively about current or former organizations/bosses.
But the worst thing that I have heard of someone doing in an interview is picking at pimples on his face!