Ask someone why they have not made a career move, and they will usually tell you about market timing, golden handcuffs, or a lack of options. Beneath those practical excuses lies a much more fundamental dilemma: Which outcome terrifies you more: failing at something new, or succeeding for another five years at a job you have already outgrown? For high achievers, the second option often feels safer on paper. You know the environment, the salary clears every month, and you can execute with your...