Ghosted, after putting in so much time and effort. I don't think that there is any excuse for ghosting candidates, after multiple follow ups. Its understandable that sometimes situations might have changed, say the role is being put on hold. But the least one can do is to acknowledge that they are working on providing an update. There is a high level of accountability problem across the board for recruiters these days. They have one job (literally there is someone else for scheduling). I won't be naming names, but what goes around comes around. After all Its a small recruiters' market.

Respectful, challenging, expecting previous experience in the area. Understanding of processes and common challenges, with real examples. Discussions based on description of real scenario situations. Very senior people working and interviewing candidates.