What is the business model behind motivating someone to deploy Twitter bots?
However, other people creating fake accounts certainly might benefit them for the reason you suggested - but these bots were not made by Twitter.
(not being facetious, I'm honestly curious, as someone who does not use Twitter or Facebook or any of these other social promotion services)
As an individual with lots of followers, you could advertise paid gigs, like "I will mention your product to my 100k followers for $10". Then somebody like Kim Kardashian can charge $100k or more per "endorsement".
There's a whole vaporware "value chain" here.
The user withdavidle posted this above, which is a great article: https://medium.com/i-data/fake-friends-with-real-benefits-ee...