ReliaQuest interview questions

Their corporate recruiter reached out to me via LinkedIn to see if I was interested in their Enterprise sales role there. I then had an initial phone screen. It went completely fine. But I didn't hear back until the following week, no big deal. The recruiter left a very positive sounding message, so I'm thinking, 'cool sounds like a next step in the process is coming'. I call the recruiter back and surprise to me, they say they're moving forward with a couple of other candidates. What? I've had many of these first interviews in the past, but I've never been turned down for a 2nd interview, especially when the company recruiter reached out to me over LinkedIn about the opportunity. What's that all about? They saw my background, they asked me if I was interested. It's like they saw me as a good back-up plan just in case the other two candidates didn't work out. There wasn't any other reason why they wouldn't want to consider me. What a complete waste of time and unprofessional.