Slack interview questions

I had the first phone interview with Slack. The guy was not very friendly and not helpful, I don't like his attitude. (He )He asked about my background and skills. The interview was nothing special, seemed like a phone screen but have no idea why I got rejected. The overall impression they gave me is that they are not really seriously to consider hiring new grad candidates. They schedule lots of interview for marketing but not really hiring so many people.

Applied online. A couple days later got an email from a recruiter asking to schedule a brief phone interview. I scheduled for the next available time, which was 2 weeks later. On the day of the phone screen, I get a call from the recruiter from a private number a minute behind schedule. I answer and the guy on the other end of the line quickly asks me if I have time for the interview, as if he is in a rush. Of course I have time, and he asks me to tell him about some of the work I've done. I start going into some of my work, and it's just silent on the other end of the line, well actually, it sounded like this guy was in a call center, and the connection was really crummy, but the recruiter doesn't seem interested at all. After that, he asks me "Why Slack?" and tells me that the interview process after this goes to a brief chat with the hiring manager and then a technical challenge that is due a week after it's given. After that, if they like you they fly you out to do more interviews. Unfortunately I got an email a day later saying that I wasn't moving forward. Overall, not a bad experience, but it didn't really seem personal, or like they cared, which was surprising.