I applied online and was invited to book a telephone interview about a week later. This "interview" was more of a friendly chat with someone from HR a chance to talk about myself, my situation, and general motivation for applying. I also got to find out a lot about the company which was nice, and I left with a good feeling about working there. The next day I got invited to book the next telephone interview which was with someone from the Insights team. This was a slightly more formal interview assessing motivation, how my experience/skills were relevant, and some simple probability questions. Around 5 days later (including weekend) I got invited to a third and final interview which was a Microsoft Teams meeting with two senior members of the Insight team. This time I was rigorously assessed on skills, motivation, and situational-based questions relating to the role. A decent amount of the interview was taken up by maths questions focusing on probability which got progressively harder. The interviewers were very friendly and personable, but the maths questions were pretty difficult especially when on the spot and nervous! About a week after, I was informed that I had not got the role as I didn't do well enough in the maths section of the interview.