Forte Research Systems Project Manager interview questions

The process seemed disjointed. I went straight to an interview with the hiring manager, skipping the HR phone screen. Then was put through two additional panel interviews. Finally, I was told I was to have one more panel interview with the team, but literally a few hours before the interview. Interviews were with different stakeholders in the firm and having different relationships with particular software. Interviewing with Forte was one of the most unprofessional experiences in my life. I was promised a fourth and final interview and then hours before the interview, HR interviewed me to tell me the job was filled. Who promises a final candidate an interview and then declines right before it happens? It would be more professional to put everything on hold while you are negotiating a final offer with another candidate then to waste the time of other candidates. I can see from the reviews that this has happened before so it seems like this is regular occurrence and must speak to the culture of the firm and its lack of care for its employees.