CBRE Manager interview questions

It was an extensive Interview Process with 3 phone interviews and 3 in-person interviews. I was led to believe I had the position and would be contacted in the next day or two to finalize, but no call came. I followed up and was told they were sorry and that everyone was busy, but they would be back to me by the end of the week with next steps and again, no contact from the company. I followed up one more time with the HR contact, she thought they had hired me and was going to get back to me, but she never did. It was very disheartening as I had spent about 15hrs in interviews and no one had the courtesy to tell me they were not hiring me. Throughout the interview process, everything was positive, but their lack of finalizing anything and just letting me hang out there, really soured me on the company. Very unprofessional.