A recruiter will message you if they think you are a good fit for the position. They probably obtained a copy of your resume via career center of your school. When selecting potential hires, they have chosen finance majors, marketing majors, government majors, English majors, math majors, international relations major, etc. Basically, there was no specific major they chose for this position. There were about 3 rounds of the interview process for the Business Analyst position.
First round was simply looking at GPAs, varsity sports (if applicable), extracurricular activities, getting to know your personality, etc. If you've made the second round, you get invited to a special happy hour (Not sure if this applies to every school), where you can try to push your way through 40 other students who are surrounding about 3 Business Analysts who currently work there. Afterwards, you go into your second round interview the next day, which is slightly more difficult than the first; this is where you work on case interviews.
Here's where it gets tricky. Every interviewer is different and will judge you based on how he or she thinks you will fit. Some I've heard will want you to finish the case, while others could care less. Ultimately, it is all a matter on how well you COMMUNICATE! For my case, I was suppose to figure out whether or not it was worth it for a franchise of Subway to participate in the $5 foot long deal. They gave me some parameters and initial conditions to work with. Throughout the process, the math was not difficult, especially for someone who is a Math major. The most difficult equation I used was Revenues - Expense = Profit and some other tricks with proportions and percentages. What probably killed my interview was after discussing the initial conditions with my interviewer, I sat there for 10-15 minutes silently and ended up creating an entire systems of equation. So basically you can solve your problem by plugging in numbers; once you get the result, it should tell you whether "yes, this is a good investment" or "no, this is not a good investment". After creating an entire model, I walked the interviewer through it.
In retrospect, this was probably not what the interviewer was looking for. First, creating an entire model probably went way above the call of duty (especially for a business analyst, this was probably a job for financial engineers or modelers). Second, the interviewer probably did not understand the equation; if you are not a math major, it will probably be difficult to understand all the random variables I threw in. Lastly, I did not pass the COMMUNICATION test. In a case interview like this one, you are not suppose to be a lone wolf and try to solve something on your own. The whole point is to talk with your interviewer and try to solve the case together. Overall, my interviewer was highly surprised that I solved the entire case on my own, while also adding a bit of mathematical spunk to it; simultaneously, my interviewer was also very perplexed at my work. If the interviewer has no clue what you're doing, despite an elaborate and logical explanation, it's not a good look.
After also getting feedback from fellow students who interviewed, most who made it to the final round, didn't even finish or know how to finish a case correctly, but went onto the next round because they were able to communicate and talk for 30 minutes.
In my honest opinion, I don't agree with the way the interview went. I rather have someone create a model to ensure efficiency and consistency and prove their intellect than someone who doesn't even know how to finish a case. But again, you have to look at the position title, what the tasks are within the position, and what the company is looking for. The interview gave me an idea of what the company, the employees, and the office could be like. It didn't fit with my character and my abilities, so it was probably a good thing that I did not make it to the final round.