The interview process is rigorous, but it gives you a great idea of what your actual work will look and feel like. If you don't enjoy the assignments, you won't enjoy the work.
There are two take home assignments followed by a day of three or four live interviews if you do well on the assignments.
The first assignment is a quick screening tool, but still requires some thought and attention. The second assignment is complex and and probably the most important part of the interview process. It takes a good deal of time to complete, but it is a great representation of the work you will actually be doing on the job. If you hate the assignment, or find it tedious or boring, you won't like the job.
(As a side note, I see another review complaining about "gross" vs "net" billings. Companies often have their own definitions for financial metrics, which you can look up very easily in their financial filings. A certain company defines gross billings as "gross amounts...net of estimated refunds.")
In the live interviews, you go over the take-home assignment in one and then the others are typically standard behavioral interviews. There's nothing tricky in the live interviews, but they're important.