Moda Operandi Senior Software Engineer interview questions

Initial short phone screen with a VP, followed by a HackerRank coding challenge that was a good test, followed by a four hour onsite with an hour with different people for each of system design, object oriented design, coding, and experience/interpersonal. I thought the folks that interviewed me are smart and likable, and asked good questions. The two coding challenges I took were aimed at understanding my ability to design an algorithm then to discuss its efficiency. There was some ambiguity in the questions but I asked questions and got good answers. The interviewer was prepared for those questions and was, clearly, evaluating me on my questions and unstated assumptions. I respect that.

Every step of the interview process was ok except for the on-site. I started Moda Operandi interview process by having a chat with HR. After that I had a phone screen with a senior engineer where I did a coding exercise. Upon completing the phone screen's coding challenge they invited me on-site. The itinerary given to me was not followed once I arrived onsite. They started my interview about 15 minutes late, a randomly chosen engineer interviewed me and not the VP of engineering that was scheduled since he was "tied up with another candidate". I was taken to some back room closet like office since the office reserved for my interviews were taken totally disregarding the reservation on the office window. Here I was asked system design questions which was pretty straightforward. Next, I finally met the VP of engineering we discussed my background and projects I had worked on in the past. He went into the details about each one. After that, it was time for the next interviewer, but he happened to be out of the office that day so the VP of engineering interviewed me again for another round. After that it was a 2 on 1 interview. This was coding exercise to be coded on the whiteboard. The onsite process was not great. It seems they had their mind already made up on a candidate. Also having 2 out of the 4 engineers that were supposed to interview me being out of the office that day along with the HR coordinator didn't seem like things would go in my favor. I was rejected in the strangest way ever in my career. After a week from my on-site I received an email from HR asking to have a chat with me with no additional information given. Finally we were able to connect and I was asked how I felt about the the team, role and company. So explained my excitement about the role and thought an offer was being extended. Nope! After being asked that and explaining myself I was told they went with another candidate. Bizarre! I feel the process from the on-site interview onwards was a waste of my time and unprofessional. I would not recommend any of my friends or colleagues to interview at this company.