Awkward moment Marlon Wayans told Tiffany Haddish she's immature and unprofessional live on TV

They say that honesty is the best policy; tell people the truth and your life will be plain sailing.

But as this clip will show you, sometimes it's better not to know:

Marlon Wayans has been around the block, writing and starring in some of the biggest comedies of his generation.

So it's fair to say that he knows a thing or two about the film business and professionalism, you know, how to behave on set.

And during an interview a couple of years ago, he was confronted by Tiffany Haddish over why he never cast her in a flick.

The comic was standing in for Ellen DeGeneres, and used her platform to get some answers from the Scary Movie star.

ABC/Ellen DeGeneres Show

Referencing a role that apparently called for a 'Tiffany Haddish type', which she failed to get passed the audition stage for, the 43-year-old said: "I know we friends and I know you love me. I love you.

"You have helped me in so many different aspects in life, gave me some great advice. But this what I want to know. I have auditioned for so many of your movies, your family. Why do I never get cast?"

Put on the spot, Wayans gave a wry smile and was pretty honest with her - a little too honest, you could say.

And it was pretty brutal to watch, it has to be said.

“Me and my family always say you’re funny," he kicked things off. “As producers, you hire and cast people.

"You were always funny, but you were always on 10. And sometimes you just be inappropriate."

He went on: “It’s like a love scene, and you want to sit on the actor’s lap and fart."

ABC/Ellen DeGeneres Show

"And it’s like, ‘No, Tiffany, it’s not for this scene'. So it was maturation that [had to] hit you.

“It’s like, for me even, right now I feel like I’m ready. I’ve been preparing 30 years for what’s happening to me now.

“It all happens to you at a certain time when maturity and that stardom hits you. Never nothin’ personal."

Adding: "We love you. Always thought you was funny. Me and my family, we proud of you.”

See what I mean? While honesty is the best way to go most of the time, it can also sting.

Maybe next time, Marlon, you could just not, eh?