尽管库克自2011年接任苹果CEO以来，将年销售额从1080亿美元提升至4160亿美元，经营利润从340亿美元增至1330亿美元，市值从约3500亿美元飙升至4万亿美元，创造了近1万亿美元累计净利润的无与伦比成绩，但他可能很快离任。类似经历的还有沃尔玛总裁麦克米伦（12年在岗）、伯克希尔哈撒韦的巴菲特（60年掌权）和摩根大通的戴蒙（20年），这种长期任职的“马拉松型CEO”在标普500指数公司中占比接近20%，这类公司市值中位数为590亿美元，五年总股东回报率达93%，均高于新任CEO领导近三年内企业的两倍和三倍。

然而数据显示，85%的接班人来自公司内部，其中66%未能超越前任，相比市场整体表现，有近半数甚至落后于标普500指数。事实证明，长期高绩效管理者的接班人往往难以胜任，通用电气用了17年和两次失败尝试才找到韦尔奇的合适继任者，耐克和波音同样经历了换帅不畅。继任者不必完全失败，只要表现平平就容易让投资者失望。

为降低这类“均值回归”的风险，公司需要高度重视接班人计划，不仅要及早发掘和培养下一代人才，还要持续更新名单，动态适应环境变化。专家建议，尤其在当今变化剧烈的时期，企业不应只在内部找人，还要考虑更多外部候选者。作为全球市值最高的公司之一，苹果下任CEO还需克服中国产业链依赖、补齐AI布局短板，并推出继iPhone后的“现象级”新产品，否则极难复制库克时期的辉煌。

Despite Tim Cook’s outstanding record—increasing Apple’s annual sales from $108bn to $416bn, operating profit from $34bn to $133bn, and market cap from $350bn to $4trn since 2011, generating nearly $1trn cumulative net income—he may step down soon. Other “marathon CEOs” like Doug McMillon at Walmart (12 years), Warren Buffett at Berkshire Hathaway (60 years), and Jamie Dimon at JPMorgan Chase (20 years) highlight a trend: nearly 20% of S&P 500 firms are led by CEOs with a decade or more of tenure. These companies outperform, with a median market value of $59bn and five-year shareholder returns of 93%, double and triple the metrics for firms led by newer bosses.

Nevertheless, succession data is sobering: 85% of successors are internal, but 66% deliver lower returns than their predecessors and nearly half actually underperform the S&P 500. Firms struggle to replace long-serving, high-performing CEOs; GE took 17 years and two failures after Jack Welch, and Nike and Boeing also found strong follow-ups difficult. Successors needn’t be disastrous to disappoint—mere mediocrity often frustrates investors after legendary leadership.

To minimize risks of this mean reversion, companies must prioritize and update succession planning, identifying younger talent well in advance as business conditions evolve. Experts urge boards especially today to consider external candidates rather than relying solely on insiders. For Apple, this is crucial: the next CEO must tackle over-dependence on Chinese supply chains, craft an AI strategy, and deliver a hit to rival the 18-year-old iPhone, or risk falling short of Cook’s legacy.