Consulting is a very competitive field, with most firms receiving tens of thousands of applicants each year.
Regardless of one's natural intellect and career qualifications, I continue to be amazed by the number of emails I receive from people who put in only one or two days of preparation, got rejected and are surprised by the outcome.
To be fair, many of these people did not know about the consulting field and did not realize that preparation was necessary until a day or two before the interview. This we can legitimately chalk up to unfortunate circumstances.
Others knew they needed to prepare, had ample time to prepare, but thought they would wait until they got the interview before doing so. The problem with this approach is you often only get 3 - 5 days notice between when you find out you have an interview and when you are expected to show up for it.
Unless you are brilliant, this is really hard to do. And I have met many people in this category who really are that brilliant. For the rest of us (myself included), it takes more time.
The difference in my performance (given the same raw talent) with preparation vs. without preparation is probably a difference of 10 times. Preparation matters a lot.
Preparing allows you to showcase your talent... how naturally good you really are. Most candidates who don't get offers, and especially those who get past the first round but do not get past the final round, have the raw talent, but were not consistent enough in their performance to get the offer. This is solved 100% via practice.
To put it another way lets say you spent the time to study my Case Interview Secrets videos (10+ hours), went through Look Over My Shoulder® 5 - 6 times (60 hours), and did 40 live practice interviews with a practice partner (40+ hours if someone gave you interviews, 80+ hours if you had to reciprocate and give them one too).
This is over and above the time you spent reading my emails and articles (est. 10 hours).
Look at the total prep time you put in, it is somewhere between 120 hours on the low end and upwards of 160 hours on the high end.
If you are competing against someone with similar qualifications, and similar skills, consider the following: You put in 120 - 160 hours of preparation, and the person you compete against puts in five hours. Who is more likely to get the offer?
Common sense suggests all else being equal, the person who prepares 25 - 30 times more will have a major advantage.
This is not some super insider secret. It is just common sense. But common sense is rarely common practice.
Now let me circle back to something I mentioned earlier about comparing the performance of a candidate who prepares for 120 - 160 hours vs. one that prepares for five hours.
Let me do so by sharing a story.
When I was at McKinsey, two things became very apparent to me about my colleagues.
1) It was impossible to be smarter than them.
2) It was impossible to work harder than them.
You could be as smart as them... you can work as hard as them... but it was just not possible to beat them in both.
Hence, the culture at McKinsey was very much that of being in a very high performing peer group -- kind of like the reason why top athletes love playing with other top athletes on the "All Star" team.
Now when you apply these two concepts to the interview process, here is what you will find.
In Round 1, it is possible that you are smarter than the other candidate. The quality of the Round 1 candidate pool has wider variability.
But, as you move from one round to the next, the average intellectual horsepower of the competing candidates increases.
If you barely passed Round 1, it is unlikely you will pass Round 2 on your talent alone.
The bar is moving higher and higher and you will be surpassed, unless you out-prepare the competitors.