IQVIA Software Development Engineer -3 interview questions

I finished 3 rounds of technical interview and 1 Hr interview. The whole interview process lasted a month..then after another 20 days they said this position is no longer available so we cannot hire you. So it is a waste of time to go for interview and expect them to hire. I had a very bad experience of this type where the whole process was too long and then they realize that they do not need that position itself.