The 40-year-old designer said it was a struggle to prove herself in the fashion industry after initially rising to prominence for her pop career, reported Daily Mirror.
"For a long time there, I was a bit of a laughing stock. And while everybody was busy laughing, what was I doing? I was laying the foundation to what I have in place now," Beckham said.
"Everybody said, 'Well it's never going to work because a celebrity can't do a line (but because) everyone thought it was going to be rubbish (it took) the pressure off a little bit. I didn't go into this to prove anything to anybody other than myself," she added.