Why was Olive Kitteridge chosen for Pulitzer Prize?

"Olive Kitteridge" did not win the Pulitzer Prize. It was a finalist of the 2009 Pulitzer Prize for fiction, however, Cormac McCarthy's "The Road" ultimately won that year. "Olive Kitteridge" did won many notable accolades including; Fiction Award for Distinguished Contribution to American Letters and Pen/Faulkner award, making it a critically acclaimed work.