CNH Industrial interview questions

I applied online and after 2 months a guy contacted me and scheduled me for 5 rounds of interview including 2 in person interview ( on site) and 3 virtual interview which took almost a month. i talked to more than 10 people with different backgrounds form HR department to engineering and test and many other departments. i had a friend referring me to this position so i did everything company asked me. after all this interviews and driving to the site 2 times with i didn't hear from company for months and then my friend at the company talked to the hiring manager and the guy told my friend that i was a great candidate but i told them i was not interested in the position. how am i not interested in the job and i still go through 5 rounds of interview?

What a garbage place to interview. had an interview, went great, was told it would be a couple weeks before hearing back. 1.5 months later and nothikng, hr wont answer