Knockout Gaming Software Engineer interview questions

No good experience at all. I sent an email and got a phone interview scheduled. When the day came, no one called me. I was told the following day that the manager was not in the office. I barely got a "sorry". When I finally had the phone interview it was an easy one: project where I had worked and similar stuff. I was told that I would receive a home exercise, which I did. After sending it, nothing. After 3 weeks or so I got an email telling me that I was not selected. The implementation that I did was correct, so I know that was not the reason. If they were not willing to hire me from the beginning, I don't know why they wasted my time. I didn't get any feedback either.