ONCI Machine Learning Engineer interview questions

Initial call with their HR, then a 1 hour technical interview. Afterwards 3 additional technical interviews and 1 additional HR interview. Everything seemed to be going smoothly, I completed the entire process and was told I'd get an answer the following week. The answer never came. They ignored my emails for a very long time, only to end up telling me they decided not to hire anyone. Their decision is fair, but ignoring all emails and not getting back to a candidate who spent hours preparing and interviewing is disrespectful.