Simple answer - our airwaves, stream of thought and consciousness, and what we believe to be true are chock full of lies - intentional and unintentional.
On top of this, we all react to information with our own expectation biases and preconceived ideas. This colors incoming data to the point that what we perceive to be “truth” is in fact many shades of gray.
In other words, there are the lies imposed upon us by others and the lies we impose upon ourselves. We are very good at recognizing the lies of others who we do not agree with (fake news) and very bad at recognizing the lies we impose upon ourselves or by those we agree with (bias).
It is an interesting study perfectly illustrated every day in all kinds of media to include FR. It is made far worse by the lack of a scientific process where limited or selective data is used to form the final hypothesis to fit a desired outcome and data revealed later is largely ignored or discounted in the 24 hour news cycle.