I've never really understood Uber, in London there's a company called Addison Lee, do basically the same as Uber London and have for years, have loads more cars

I've never really understood Uber, in London there's a company called Addison Lee, do basically the same as Uber London and have for years, have loads more cars, more experience and charge about 20-30% less than Uber. I've never been to any of the other cities where Uber operates but I can't see why anyone would pay more for Uber over Addison Lee. Have I missed something?