Chalk up to

Chalk it up to fear that he didn't finish.

“You can chalk it up maybe to, as one of my friends says, a nautical superstition,” he said. “Maybe I read too many Greek tragedies. I don't believe something’s going to happen like that until it’s happened.

Some of the best pre-mortems for Steve Ballmer, out-going CEO of Microsoft, have chalked up the company's problem to the "innovator's dilemma."