Miley Cyrus gets "nervous" on the red carpet.
The 'Wrecking Ball' hitmaker says she only sticks her tongue out when she gets her picture taken because she gets "embarrassed" at being the centre of attention.
Discussing her infamous expression, she explained: 'Its because don't like getting my picture taken, I kind of get embarrassed.
"You don't see it, on the red carpet the people taking your pictures are yelling at you. and it gets you a little nervous. They're screaming I don't know what to do so I just stick my tongue out because I don't know what else to do.
"People are doing it, Madonna's doing it. It's all good."
The 21-year-old singer also urged Justin Bieber to build a club at his house in a bid to keep out of trouble.
Asked by talk show host Jay Leno what advice she would give the troubled teenager, she said: "You've got a lot of money. Pay people to make sure you don't get in trouble, and party at your house.
"Buy a house, and add a club to it."
The former 'Hannah Montana' star spoke about the criticism she receives, insisting it isn't always fair as none of her antics are "illegal".
She said: "You know it's funny cos today I was looking, my fans had put all these mugshots up and they were like, 'I don't see a Miley mugshot yet.'
"I get the most flack from anybody but I don't do anything illegal.
'I'm doing a lot of s**t, but I'm not doing anything illegal - so that's alright. 'Everything I do is legal in California."