RBC Senior Software Developer interview questions

I applied Online for this job. I received a call from HR within a week. It was introductory call and then my Phone Interview was scheduled with Hiring manager. This was purely behavioral interview with no technical flavor to it. After this interview I received take home technical assignment over email with requirements written in Notepad and with note to code as per my understanding of requirements. There was never a call to discuss my understanding of requirements and solution that I see fit. After submitting technical assignment, next response was that They have decided to not go ahead with my profile. I fail to understand without ever interviewing me for my technical abilities they shot down my profile based on some assignment. I never also got a chance discuss solution I implemented and why I implemented it that way. I can understand that my solution may not be solution they were looking for but again requirements clearly said to implement as per my understanding (And I also clearly mentioned all my assumptions) and unless they asked me to build house and I built Car which I think is highly unlikely, I feel this interview process is very unprofessional and just wasted my time working on assignment which I never got chance to discuss this. My suggestion to fellow applicants is ask for technical interview first rather than wasting your time on some assignment which they may not look at also.