Jack Shafer credits infighting:
Every source leaks for a reason, and it’s usually not about preserving the constitution and the American way. As Stephen Hess writes, sources have many reasons to leak. They leak to boost their own egos. They leak to make a goodwill deposit with a reporter that they hope to withdraw in the future. They leak to advance their policy initiative. They leak to launch trial balloons and sometimes even to blow the whistle on wrongdoing. But until contesting evidence arrives, it’s usually a safe bet that a leak is what Hess calls an “Animus Leak,” designed to inflict damage on another party.