Meraki Developer interview questions

In the last two weeks, I have been undergoing interviews for a position at Cisco Meraki. There were four technical rounds, including a live coding session in the first technical interview, followed by three more technical interviews with questions. Additionally, I had two interviews with the HR team from the consulting agency handling the recruitment process. The first three technical interviews with the Meraki team were great, very positive experiences with respectful individuals who were mindful of the interview duration. Unfortunately, I cannot say the same for the last interview. He arrived almost 10 minutes late, which was understandable, but his demeanor was not as friendly as the previous interviewers. Throughout the interview, he seemed bothered, and his microphone had intermittent issues. The interview, initially scheduled for 30 minutes and conducted during my lunch break, ended up lasting 50 minutes because he did not adhere to the allotted time. Despite being able to answer the technical questions, I occasionally had to ask him to repeat due to the difficulty in understanding his accent. After three successful rounds where I was approved and praised, the fourth round, unfortunately, turned out to be a significant disappointment, resulting in my elimination from what was supposed to be the final stage of the process. It was a frustrating and exhausting experience. I believe a fourth technical round was unnecessary, especially after three thorough and enlightening rounds. I hope the selection process improves, as I was genuinely excited about the prospect of joining the company, and now I have a different, negative perception.