I applied online and received an email a week later asking to arrange a phone interview date and time. After I suggested a date and time, the recruiter replied that the timing "was excellent". On the scheduled interview date, I received no phone call from the recruiter. I waited almost 20 minutes. I also emailed her asking if another date would be better for her (I did not have her phone number). I was completely ghosted at that point. I'm presuming they chose another candidate between the time of her initial reaching out and the interview date (which was a week in between). No communication comes across as unprofessional with no care of wasting one's time.