Singer Rihanna believes that she has not yet reached "the top" of her career and never wants to feel "comfortable enough" to say she is.

The “Umbrella” hitmaker may have sold millions of records around the world, and also ventured into fashion design and acting, but she never wants to get complacent about her success as she thinks it would make things go wrong, reports femalefirst.co.uk.

"What is the top? I don't think you're ever at the top. If you ever feel you're at the top, there's only one way to go and that's down -- and I don't ever want to feel comfortable enough to say that," she said.

The 27-year-old knew she wanted to be a world-famous singer from a young age.

"I always had a big dream and it's only now I look back in hindsight that it was a really, really, really big dream for a little girl from a really small island (Barbados). I wanted to sing and I wanted to sing like the big ones -- Mariah (Carey), Celine (Dion), Whitney (Houston), Destiny's Child," she said.

"These were women from all spectrums of the globe who made music that could be heard all over the world and I wanted to do that too."

Rihanna added: "This was so far from the reality of my life that it was hardly even possible but back then it didn't seem strange at all. I really believed it could happen.” .