How do you know that Britney Spears is a big success as a singer?

Britney Spears is recognized as a major success in the music industry due to her numerous chart-topping hits, including classics like "...Baby One More Time" and "Toxic," which have solidified her status as a pop icon. She has sold over 100 million records worldwide, making her one of the best-selling female artists of all time. Additionally, her influence on pop culture, fashion, and Music Videos, along with multiple awards and accolades, further attest to her significant impact and success as a singer.