Radiant Vision Systems Supply Chain Manager interview questions

A very slow process. I had two phone interviews, one with HR, then with the hiring manager. Each lasted around an hour. Then I had a four hour in person interview. They scheduled a 30 minute phone follow up and called me 25 minutes late. They said they would be in touch with me within two weeks for the next step, which would include yet another in person interview. I never heard back, despite following up, and their assurance I would hear back either way.