How different is the actual consulting process from a case interview? (I mean to ask you that, in a case interview candidates are given cases and are expected to provide solutions based on facts and data. But, in a real life business problem how do consultants deal with such problems.)
The case interview process very closely mimics one aspect of the day-to-day life of a consultant. This aspect is problem solving, analysis or problem structuring.
The part of the process that case interviews does not mimic is data collection.
For example, in a case interview the candidate says, "I see that sales have fallen 10%. Since sales is comprised of quantity sold x price, do we have any data on how unit sales have changed during this time period?"
In a case interviewer, the interviewer gives the answer. "Unit sales have fallen 10%".
In real life, the consultant might as the engagement manager the same question. Instead of the engagement manager giving an answer, she might say something like, "I agree that's the right next question to figure out the answer to. Why don't you go to talk to the CFO's office, get a finance manager to pull the data from the sales tracking system and let me know what you find."
In real life, this might take a day of phone calls, emails, meetings to get the data... and a day later, we discover unit sales are in fact down 10%.
So the case interview process is a time compressed version of real life consulting that excludes the data collection part of the job.