Autodesk interview questions

The assessment day involved a group project, a 1 hour coding test, and a 1 hour interview. The interview was split into 3 parts: a motivations part, technical questions, and a puzzle.

Had a screening round with the Hiring Manager and had 3 more technical rounds after that. Interview level difficulty was medium. Nothing too hard and everyone I spoke to very enthusiastic about their team and their work. Finally after all the rounds were completed got mail from HR that feedback was positive and we had a call discussion around compensation and Joining date and post that I did not receive any communication after that . However 2 weeks later found out they interviewed one more candidate and decided to roll out the offer to the other candidate. What I am failing to understand is if you don't want to give me an offer or were never interested in me why bother interviewing me and waste my time as well. Because of the fake offer you guys proposed I declined an offer from an other company. I would never interview here ever and would advice others to keep your options open even if you get an offer from here.