Henry Paulson blames the borrowers

I am listening to Henry Paulson's speech and I note that in his first few paragraphs -- he blames the borrowers not the banks. He said that "borrowers took out loans they couldn't afford" and this is the root of this crisis. As if the trembling would- be-home owner, who was swayed by a so called "expert" bank official offering a variable rate mortgage with a balloon payment bears all the blame. The question remains to be answered -- WHY DID THE BANKS GRANT THESE LOANS?