As many HR specialists were correctly saying at the start of the year, employee retention is a hot topic now that companies are hiring again.

FORBES: Are You Paying the Right Price for Employee Loyalty?

And though Google doesn't comment on the specifics of its hiring process it likes to maintain an air of mystery, which has led to a cottage industry of samizdat Google questions passed among hopeful future employees and curious outsiders former and current Google HR specialists have shared rather freely with me what it is that motivates the way they interview job candidates.

WSJ: How to Ace a Google Interview