What factors contribute to the fragmentation of HR and payroll ecosystems?

Payroll originally grew out of a pen-and-paper model, which means that it's hyper local and also very specialized into specific industries. 

Also, it's a very sticky business model. Therefore, you can verticalize it. Instead of having to take over the whole market to be able to build a big business, you can build payroll and get 100 customers, then sell and cross-sell a lot of other products on it and build a very successful business. 

Secondly, there is some form of consolidation at the business level—ADP has bought a lot of these companies—but that doesn't mean that there’s consolidation at the systems level. Underneath ADP, you have 17 different types of payroll systems and 17 different connections.