Uinsure interview questions

The interview process was over the space of four weeks. The first stage is an initial call with the head of engineering to get an insight into the business, which was interesting, The duration being thirty minutes. The second stage is a take home coding kata, which tests you on your refactoring abilities. This took about two hours. The third stage is a technical interview with two other technical leaders within the company. They go through the kata and question your approach and see how you take constructive feedback. This was a great part of the interview process because the devs were insightful and appreciated your time and effort. This interview took two hours. The final stage is where it went downhill. You're given a very abstract brief for a presentation. I spent just under a week prepping for this, taking what I thought was a good approach based on the brief. The interviewers are the CTO, COO and head of engineering which was a first for me, unnecessary for the role applied for. The presentation lasted just under thirty minutes. During this time I could tell the interviewers weren't really interested and were clearly doing something else on their screens. I was hardly asked any questions at the end. I knew instantly I did something wrong. This interview was supposed to be one hour and thirty minutes, however it lasted just below forty minutes. In total, the interview process took over five hours, taking in the time it took me to prep the presentation, just over seven hours of my time was taken up for this interview process. The feedback I got for not getting the role? "They didn't stick to the brief" Cool. My feedback would be, not to have the c-suite in the room, it's off-putting. If you have time left over and the person hasn't covered the vague brief but clearly put a lot of time and effort into the presentation, why not ask them questions they may have missed? Your brief isn't appropriate either, something politics use and hard to predict something like this when you don't know what the company culture, teams, motivations and drives are.