Had a "surprise" interview over the phone with the hiring manager approx. 20 days after I applied online (usually I expect a call or an email from HR or recruiter to schedule a time). Even though I was not totally prepared I believe I did well and went for the 2nd phase to visit the Austin office and to meet and interview with the team.
A couple of weeks later, I had a face-to-face interview with the hiring manager and 3 different folks from the team. They were all nice, professional and receptive even though they were reading questions from a script. But I never heard back from the company after that day.
There is nothing more frustrating for a candidate when they dedicate time and prepare to give their best and NEVER hear back from the company. Extremely unprofessional no matter how good or bad the interview was.