Cover interview questions

I had a phone screen with the recruiter asking general questions about my experience, availability and salary expectations. I was then given a coding assessment in which I was provided a third-party car inventory API and told to build an Auto Classifieds platform. I was given a set of mandatory features and was told I have the freedom to build the application as complexly as I wanted to in ~4 hours. I completed the assignment in the allotted time frame and was told I would hear back within a couple of days. I heard nothing for 2 weeks (unless I followed up to ask what was happening, to which, again, I got more delays), and when I did hear back, I was told they weren't moving forward because they had wanted to see more work on the backend. It was a bit shocking given the fact that they had supplied me with a third-party API which did everything you would expect from the backend of the kind of application they had outlined. I also found this to be very weak and unconstructive feedback given the amount of effort I had clearly put into my application. Based on the requirements I was given for the assignment, the feedback I received, and the number of delays in between, I found this process to be a waste of my time and really inconsiderate of candidate's experience.

I submitted an application through their website, and was contacted by a recruiter. I had an incredibly long phone interview (over an hour) with the recruiter, who asked vague questions that weren't at all relevant to true content creation. She promised to follow up after I emailed my portfolio, and never got back to me, despite multiple emails sent her way.