Snap interview questions

The worst recruiting process I have had in my life! I got contacted 4 months after sending my application. The first interview was a friendly visio chat with an HR. After that, I was invited to a second interview (also visio) that would be technical with the hiring manager. It was supposed to be a live coding challenge to which I prepared very seriously. On the day of the interview, the hiring manager showed up one hour after the scheduled time. He said that the HR messed up with the timing. The interview turned out to be a discussion where I had to present myself, no live coding challenge... After that, I was invited to an onsite interview that was composed of 4 interviews in a row, starting at 09:00 am and finishing at 03:00 pm. This interview got rescheduled 4 times over a month, with less than a 48 hours notice each time. The 4 interviews were technical and extremely difficult with plenty of difficult and extremely trick questions (and I wonder why. It was completely disconnected from the reality of a day-to-day embedded software engineer life). At the end of the day, I knew I wouldn't get the job but I never received a feedback. Not even an automatic message.

The first round consisted of a remote technical interview that wants to determine whether the interviewer understands the basics. The second round consisted of a more in depth project and a behavioral interview.