You drop things on your calendar to accommodate their desire to have quick interview after interview, do a 3 hour long online assessment over your weekend to accommodate their quick timing, spend hours "interviewing" with multiple people who ask more and more very pointed, strategic questions about how you would solve or address an issue they have (so much so, that you feel like you need to send them a consulting invoice post-interview) and then nothing...not even the courtesy of a response from them. I had to press the recruiter to get a determination and received the response "decided to go with someone else."
I should have known things were not kosher as the positions are posted for over a year, represented by multiple recruiters, as well as their own sites, AND the job remained obviously posted through the whole interview process and remains posted today!
There are articles from recruiters about these types of perennial "interviews"- beware! Don't waste your time or talent...you're being used!
Note to XRite Management- try a little transparency, and just hire a Consultant instead. Leading so many people along for as long as you have, is just mean.