Windows Workflow Foundation (WF) was first introduced in 2006 with .NET 3.0. It is probably fair to say that WF didn’t receive the widespread adoption Microsoft was hoping for. This lack of uptake was probably due to a number of factors:
Although the WF designer offers a natural way of working, it is a very different way of developing applications and contains a new API to master.
Writing your own work flow activities was not as easy as it could be.
Handling and passing data between activities was cumbersome
Limited support for messaging scenarios and integration with WCF.
Some developers were confused by the hosting model.
A clunky designer interface made you want to poke your own eyes out (OK, it wasn’t that bad but it wasn’t that good either).