Do people realize that when they go for an interview on the impression they make on the person[s] sitting across the table, trying to evaluate them? I think not. Most of the people I know ignore the basic fact that they are the ones who are looking out for an opportunity and it is they who need to create an impression. They regard the basic interview process as one in which they just need to write something on their CV and expect the interviewer to understand that although, it is there, they have not really worked on the same.
This practice and activity is predominantly seen with the senior members rather than the juniors. The seniors, when they reach a certain stage in their work career [5 years in Service companies and 7-8 years in Product based ones], they tend to lean towards managing people, rather than managing themselves. Hence, the failure to clear even the simplest of technical questions, which if given to a fresher, he/she would have done the same in a jiffy.