I certainly don't make a habit of doing it to luminaries of 1980s pop, but this time I do.
"I've just been listening to your new album," I tell Boy George when he calls. "It's actually quite good."
He takes a moment to consider whether the "actually" is worth hanging up on me for.
But instead he carries on, determined to prove a point. And anyway, forget what you know about the former Culture Club singer, his new album This Is What I Do is a laidback stormer which oozes class.
But it is his first full album of new songs in 18 years. Why the wait?
"I reached a point where I thought I want to make a solo record, I need to get that out my system.
"I knew there would be people going (adopts a playground insult-style voice) 'Ooh boy George', people who didn't expect very much from me.
"It's going to surprise those people, and make my real fans very happy, because they're so excited I've physically actually made a record.
"They know they're getting their hands on it, and there's been so much joy from the hardcore following that I have. This is coming out, they've got proof.
"The level of professionalism behind this project is pleasing to my audience. It's nice to make them happy, finally."
Boy George needs little introduction. He first shot to international stardom in the 1980s as the front man of one of the UK's biggest pop exports, Culture Club.
He has since sold over 50 million albums and has had top 10 hits in every country.
Singer, actor, a revered club DJ who buys about 40 records a month, artist, photographer, fashion designer...
But he has an undeniable dark side too. There's the high-profile battle with addiction (now behind him, he says).
Then there's the stint in jail. He was also convicted of assault and false imprisonment in 2008 and served four months in prison.
Has anything changed? Does he think of himself as grown up now?
"Very much so," the 52-year-old says with a laugh.
"Past behaviour, I just don't think it works any more.
"Being a mess and being sober are both a commitment and both have a certain amount of responsibility.
"They're both equally scary. You have to work out which one works for you, and I think I've done that.
"Being sober and being in control is much more glamorous than being the other way and I'm a much nicer person, so it's a no-brainer.
"I think on a day to day basis you see what a difference it makes, how my energy has changed so dramatically and how people respond to me with such surprise.
"I'm in America right now ... a lot has changed. I've not been here for seven years, and a lot of people don't know who I am. I don't get recognised anywhere.
"I've had no-one stop me and say 'Are you Boy George?' Absolutely no-one.
"One person at Customs said you look like Boy George. They were English.
"At my gig the fans know what I'm doing and they know who I am, but in the street, in the world, even in London I go unrecognised on the tube every day.
"I've been able to enjoy America in a different way. It feels like a beginning. I feel the same as when I came here in 1982. There's a buzz.
"It's been so interesting, the reactions. I've heard people say that's not Boy George. People say you're not Boy George, you're not the one from the Eighties."
He's playing at King Tut's in Glasgow on November 7. What does he expect from his Glasgow fans?
He said: "The last time I was in Glasgow I was kissing loads of people. I can't remember what club it was. It was one with the big metal bit at the back.
"The DJ box had a metal thing behind it. It wasn't the Arches, it was another one. It was a good time.
"I'm expecting Scottish people to be as lovely as they always are."