The selection process is long and tedious, full of uncertainties.
After the 3rd interview (carried out with 2 people) they ask you to do some homework to do at home for the 4th interview. During the latter, the work done is explained to 2/3 people.
Any other consulting firm would have already hired you at the fourth interview but instead they let you know that you are also in competition with other people.
Considering that I had been contacted by them, it seems very inefficient to me.
So for a consultant position that is not paid very well, you waste 4 hours of your life (plus the time for homework at home) and they waste a total of 8 hours since they always interview you in groups.