In 2017 when Sooyoung, Seohyun and Tiffany decided to leave SM but announce that they were still part of SNSD, and that SNSD will still find sometimes to promote as a group
Most people consider that it was a joke and that SNSD was unoficially disbanded cuz there was no way that some members who left a label could still promote with their group under this same label
Most people thought that they just used this excuse for their fanbase to keep hope for a reunion and not lost their fans.
And then history prove us that these people were wrong
This situation was unique in kpop and made a lot of people wonder how it can work
But now so much idols decide to take the same path by following their solo activities under a different label while still being part of their group and making group activities under their previous label.
For example Blackpink, Gfriend, Infinite, Kara, Super Junior etc....
Do you think Snsd have been pioneer in kpop even at the end of their full time group career ?