Investment Banking Analyst

I was 2 years out of college from a target school working for a FP&A team for a major retail company in the bay area. My roommate was a 2nd year analyst at Merrill Lynch Palo Alto tech group and got me an interview. Needless to say, this was a rare opportunity to backdoor into a BB - they had some attrition after bonuses and a weak 1st year class. I received a call from a 3rd analyst to schedule the interview and a week later, (phone) interviewed with that same individual and a 1st year associate. The interview itself was pretty vanilla, meaning very technical - how does $100 of a depreciation write off affect a FS, walk me through a accretion/dilution, etc. I was called in for a in-person with 2 more analysts (2nd and 3rd year) with similar questions. Ultimately, I didn't get the offer - they supposedly had over 25 candidates to fill 2 spots and I simply wasn't prepared enough.