[Z]

They were a phenomenon though - they were pretty ****e musically all things considered but they brought on so many waves of change along with them and there's no denying they were pioneers in their field. Girl bands (as we know them now) just weren't a thing before the Spice Girls brought about a change. They led a British invasion of America, they made feminism and 'girl power' cool, they were style icons, idols to women and girls alike etc... so I think all of those things contribute to what makes them among the greatest girlbands of all time. Musically, they're nowhere near the top, but when you take cultural impact and all these other factors into account, they're juggernauts. Their sales were insane.