The principal-agent problem in corporate governance arises because the owners of a firm (the principals) hire managers (the agents) to run it, yet the two parties' interests need not coincide: a manager may prefer a quiet life, empire-building, or short-term perks to the patient maximization of shareholder value. The compensation innovation of the 1990s—paying executives largely in stock options—was offered as a solution. An option gives its holder the right to buy shares at a fixed price, so it pays off only if the share price rises. Tie a manager's wealth to the stock, the reasoning went, and the agent's incentives snap into alignment with the principals'.

A substantial literature has since complicated this tidy story. Options, critics point out, are asymmetric: they reward the holder when the price climbs but impose no symmetric penalty when it falls, since an option that finishes below its strike price is simply worth nothing. This convexity, they argue, can encourage precisely the behavior shareholders fear—reckless risk-taking—because a manager captures the upside of a gamble while bearing none of the downside beyond forgone gains. Worse, options reward share-price increases from any source, including ones the manager did not generate: a marketwide rally or a wave of cheap credit can lift a firm's stock regardless of managerial performance, handing executives windfalls untethered from the value they actually created.

These observations have not so much overturned the original rationale as bounded it. The alignment options produce is real but partial—genuine where it links pay to the firm's fortunes, illusory where the firm's fortunes move for reasons the manager neither caused nor controlled. Subsequent reforms, accordingly, have aimed less at scrapping equity pay than at refining it: indexing options to peer performance, lengthening vesting periods, and adding clawback provisions, each a targeted patch on a specific way the simple instrument let agent and principal drift apart.