'Less is more - no intern has ever impressed me with knowledge coming into the internship. Many have pissed the entire team off by thinking they had knowledge coming into it. The most impressed I ever was with an intern was a kid who carried around a notebook and just wrote down everything that sounded strange. He then googled it after hours, and if it was still strange he'd ask what it meant. The most important "task" as an intern is identifying the comers at the analyst/associate level and having them like you. Each SA to full-time hire we convert is by asking that level who they liked the best.' - Wall Street Oasis
Candidates these days try to impress too much. They bring in their arsenal of credentials, testimonials and references in a bid to be selected as that outstanding one. But so few realize that the most important trait that employers are looking for is “groom-ability” and the ability to just learn. At the junior level, firms are are not looking for heroes, they are looking for someone can be consistent with deliverables, and disciplined in doing the little things well.
That said, I think trying to 'score' at interviews can be tough. On one hand, you are competing with others for the same role, and knowledge seems to be the benchmark. On the other hand, you are trying fit into the social fabric of the firm. At the end of the day, the most important thing to remember in any interview / conversation is to be genuine as a person and don't ever over-sell on your technicals and experience. A good banker is both good at numbers, communication and fitting in well.