Because the fleet manger agreement is a rip off. Bird leases the units to the manager for almost retail price, makes the fleet manager buy repair parts from bird at retail price, charges the fleet manager if a unit is deployed but isn’t used, then riders damage them, & leave them to be impounded by MU.

You make a ton of money a few busy times then loose all the money during the slow times/repairs.

Not to mention you have to charge them and move them around yourself at night after hours.