Samsara Sales Development Representative (SDR) interview questions

Overall great process, was interviewing for a new grad SDR role, went through 4 rounds, including a mock cold call. The last one was a 1.5 hour call with three different people interviewing.

1) HR screener lasted about 20 minutes, the recruiter sounded very dull and bored out of her mind. 2) They brought me to a virtual interview with 1 manager that only lasted around 5 minutes. They only asked 1-2 questions and I answered very thoroughly using STARS and they seemed content. This was a big red flag because I've never had interviews this short before. After 24 hours, they told me that they wanted to pursue other candidates. From my point of view, it seemed like they had already decided before the 2nd interview to cut me. I emailed HR kindly requesting what I could improve upon/feedback. Never heard back from them. Very unprofessional and the manager/HR seemed very inexperienced with conducting interviews.