Once you carefully prepare your patent application and send it to the USPTO, it gets assigned to an examiner. A patent examiner is an expert in the field which they examine (so a chemical engineer wouldn't be examining an application to patent a modified bicycle, for example). You can do all the best research (on uspto.gov, talking to a PTRC representative, reading Patent It Yourself, consulting an attorney or agent), and then once you send it in, what happens?! It's like it disappears into a black hole (though the USPTO has been working on reducing pendency. What's pendency? you ask. It's the length of time it takes for a response to happen).
Well, you can find out at a three day course September 9-11. Sign up is here. Find out more about the whole STEPP thing here; this just looks like the most useful for you readers out there. STEPP stands for Stakeholder Training on Examination Practice and Procedure, which the USPTO describes as "designed to provide external stakeholders with a better understanding of how, and why, an examiner makes decisions while examining a patent application"