Arm Staff Software Engineer for Systems Validation Group interview questions

First a team lead called me and asked if the validation position is okay, as first I've applied to Embedded role. After that she set up an onsite interview First we had a discussion on what they do there and what is my experience. After that she gave me a 17 questions quiz which were around embedded and compiling and gave me, i guess, like, an hour and left me in conference room alone Test was rather easy but lacked some details (for example there was a question "what is a preprocessor and what is it used for" without any context I wrote about compilers preprocessors and that was a right answer). After that she reviewed it together with me asking some questions. After that she gave me a task on designing a device which sorts 4 numbers assuming I have blocks which can compare to values couple of days later I was called to the second interview with her (teamlead's) manager. There was some dull talks regarding my previous experience, mode of work, inspirations and why arm etc, asked about salary expectations and after that I asked my questions. Next week I was called for the joint and last interview with director of engineering and HR. It was 2:1. It almost repeated the previous interview and in the end they said they will send a decision in few work days. In the end of next week another HR contacted me that they are not taking me. I asked aout the detailed feedback, HR said that didn't talk to me, so she will gather the info and contact me early next week. And never came back.