This also isn't just "length of time operating", the same row covers "applicant's history" and "history of their users", and Bird/Lime/Spin all have a very poor history here:
> From April 11 to May 23 alone, San Francisco’s 311 Customer Service Center received nearly 1,900 complaints regarding scooters. Complaints ranged from scooters blocking sidewalk access to unsafe riding in the public right-of-way. San Francisco Public Works had to impound more than 500 scooters that were blocking sidewalks or otherwise improperly parked.
I don't know if this was strictly illegal, but it was certainly flaunting explicit instructions from the SFMTA.
https://techcrunch.com/2018/03/28/san-francisco-will-regulat...
ISTR it was Lime, and this article from March seems to back that up. The other two launched shortly after because they were afraid to lose first-mover benefits. Woopsie.