"Life is easier when you enjoy what you do"
The various traits of the candidate will be evaluated based on your presentation in the interview. Answering all the questions alone may not get you selected. How you talked, how confident you are in the process and how is your body language during the interview and your alertness etc. will play an important role in your final selection. If it is a government job a person with a lot of influence and money power may get selected irrespective of his performance in the interview provided the candidate is having all the required qualifications.
'Idhuvum Kadandhu Pogum "
Even this challenging situation would ease
Once once we have cleared the screening test, we will have to perform well in the written test so that we get a call for the final interview. Based upon our performance in the final interview, we are selected for the post. While there are numerous candidates having secured impressive marks don't qualify in the oral test because of their nervousness or otherwise. But some are fortunate enough to grab a post owing to their communication skills leading to their success in the final test. To sum up both the traits are equally important.
Anyway, the point is that a very knowledgeable candidate sometime doesn't do good in interview and that is a very difficult situation because the general impression of the candidate is ascertained in interview only and so interview is definitely an important part of the assessment process.
Knowledge is power.
Believe in the existence of God the superpower.