What works and what doesn't inside Google's labs (photos)

MOUNTAIN VIEW, Calif.--For a familiar Internet property like Google, where billions of queries are made each day, tweaking a well-known system too dramatically can frustrate users, complicate once simple tasks, and have dramatic impacts on ad revenue and the bottom line.

This week LaDawn Jentzsch, user experience researcher at Google, took CNET inside Google's Usability Testing Labs at Google's headquarters here, one of the last stops for a new product before it is rolled out to the public.

In an industry known for backend programming, engineering, and algorithms, the difference between the coded intention of a product and the human experience can be vastly different.