When Tim Cook took over Apple in 2011, skeptics predicted the company's best days were over. They were wrong. Under Cook's leadership, Apple transformed from a $350 billion Silicon Valley darling into a $4 trillion cash-generating giant, with annual revenue and profits quadrupling over 15 years.

Cook's strategy focused on expanding iPhone sales globally, particularly through a 2013 deal with China Mobile that doubled Apple's handset sales. By 2018, Apple became the first public company to reach $1 trillion in market value, driven by the premium-priced iPhone X. The pandemic then added another $1 trillion as remote workers splurged on Apple devices.

Today, with over 1 billion iPhones in use worldwide and 650 million other Apple devices, the company has been cruising on replacement cycles and services revenue. However, as Cook steps aside and John Ternus takes over, the critical question is whether this steady growth model will sustain Apple's massive $4 trillion valuation in an era increasingly dominated by artificial intelligence.