AdPerfect interview questions

I interviewed in October 2021. The first step is a 1.5 hr online coding assessment. The second step is a video technical interview and I was asked to answer technical questions verbally. In the beginning of the interview, after I answered the question “why this position/company”, the employer commented: “That’s it?”. I was shocked by this response and don’t know how to react. And in the end of the interview, I was directly told that I will not be selected for next step.