1. Not Prepared Well for the Interview
Being prepared for interview can better equip you for the interview. A prior research and preparation for commonly asked questions and their appropriate answer will be helpful during the interview.
2. Not Providing Complete and Truthful Information
It is very important that you provide complete and truthful information. Any incomplete/false information can lead to unnecessary delay. False information can have severe impact on your future ability to apply for US visa. It may also cause you lot of frustration and legal actions against you.
3. Providing Incomplete Documentation
Must carry all the required documentation with complete and authentic information. Read all the prerequisites and prepare all the documents accordingly. Keeping your documentation well organized can also leave a positive impression on the consulate officer.
4. Not Carrying Appropriate Fee
US consulate has strict methods of payments. Make sure you know the method and the exact amount of the applicable fee. For example, most US consulates don't accept cash as the payment method and would prefer separate bank drafts for visa application and visa issuance fee. Refer to an appropriate source for more detailed information.
5. Providing Unnecessary Extra Information
Do not give away any information voluntarily which is not being asked. In many cases, people trying to be over confident and over smart give out more detailed answers than is required. This may trigger additional related questions which may not work in your favor.
Question: Why do you want to go to the US?
Wrong Answer: I want to see how USA is and if I like it I want to stay back with my son.
Preferred Answer: For tourism purpose and/or to spend some quality time with my son/daughter.
6. Inconsistent Information
Inconsistency in the information about what you provide in the documentation and what you say during the interview can go against your case.
7. Arguing with the Consulate Officer
Never ever make any arguments with the consulate officer. If you want some information ask in a polite manner.
8. Having Poor Communication
Poor communication is the number one reason reason that affect your case in a negative way. If you're not good in English, you should request for a regional language interpreter.
9. Having too Much Communication (talking too much)
Remember, you are the one being interviewed and not the other way around. So, keep your communication brief and to the point. Speak only when asked for an answer.
10. Appearing to be Nervous
Being confident can bring positive results. Especially, incase of visa interview where a consulate officer has to rely on limited information provided by you. Their judgment is highly influenced by the way you react to questions, your body language, and the authenticity of you answers.