The SIT Method is designed to help you generate lots of ideas in a systematic way. But how do you select which ideas to pursue? Filtering ideas is an essential part of the creativity process. You want to make sure you spend your time only on those with the most potential.
Confirmation bias is the tendency for people to only seek out information that conforms to their pre-existing viewpoints, and subsequently ignore information that goes against them. You overweight the good news, and underweight the bad news.