Cold, they make you feel like a number and not a person. Every time you answer a question, dead silence. Despite being overqualified (I've worked in customer service for over 10 years!) I have interviewed twice over the phone now with the same bad experience so won't be doing it again.
My interview only lasted 15 minutes with no situational questions so I knew I didn't get it. I said I wasn't available ONE day on the weekend, but that I could work any time on the other day (never had a problem with that before). And that was that. Typical soulless corporation.