Discover interview questions

I first got a phone call interview with the hiring manager for 45min. We basically went through my resume and the understanding about their company. On the second day, I got an email about the onsite interview. The interview was back-to-back with 5 people. Some are about software using, some are about the understanding about the business. It went well. After that, I saw my status was considering for a long time, and then on-hold, but finally was canceled. I heard that the position was cancelled somehow and did not hire at all. I was so confused, and couldn't reach anyone in their company after the onsite interview. The interview was nice, but HR are so slow...It was an wired experience anyway.