Do you get paid for the sites that you would with PW? When you come to the forums to get help, do you limit your questions purely to development work that you are doing for free?
I originally developed PW to help us all create better sites in less time, and with more fun. I'm hoping that PW is helping others to be more competitive in all ways, including financially. But recognize that PW did not come into existence on its own. Years worth of time and money has gone into making ProcessWire happen. If you are using ProcessWire to develop sites you get paid for, then you are profiting from ProcessWire. And that's fine with me, no ROI is expected or wanted--I've never asked anyone for anything. But it is disheartening to hear a user make a statement with the implications yours makes.
Form Builder is not about making a profit. I don't expect that I will ever make enough on it to offset the actual time investment on it. My hope is that eventually it will be something where the community and myself have split the cost to create. If I wanted a profit, I would go make a Form Builder for WordPress or Drupal where the user base is large enough for that potential to exist.
Form Builder is a tool that wouldn't exist if I had to fully self fund it. It's also an experiment to determine if I can reduce my client workload and substitute some of it with ProcessWire-related development that benefits all of us. But I can't substitute something that supports my family with something that doesn't.
Form Builder is here to benefit you, not me. If you build sites for a living (or even a hobby) it's going to pay for itself the first time you use it. If you previously spent half a day building a form, now you can spend minutes and get a better, more secure and capable result that can do all sorts of things with the results it collects.
Also want to note that Form Builder is something completely different from the original subject of this thread and I don't view them as similar products at all. Likewise, Form Builder is completely different from something like Zend Form or others like it. One does not preclude the use of the other and we should all keep more than one tool in our forms toolbox. I fully support Clinton's project and any others that benefit forms in ProcessWire. Forms are one of the most diverse and important aspects of web development. I feel very confident about the value of Form Builder in your toolbox, so have made it 100% refundable if you find it isn't for you (this type of return policy is pretty rare with digital products).