Lacking ambition

People close to Ma and Xie, who still live relatively close to each other in Hangzhou, said each appreciated the other's wit and sincerity and would visit each other's homes to dine, drink and play cards.

"He never reported to Ma, per se," one person said. "They spoke to each other like brothers."

Like Ma, who is known within Alibaba to speak in colorful allegories, colleagues said Xie's speech is also imaginative and steeped in historical references. An avid reader, Xie would recommend friends fantasy novels like the "Grave Robbers' Chronicles".

Who's who of Alibaba's inner circle

Alibaba starts NY investor session

He's fond of making jokes and puns, particularly over cups of his favored baijiu, a fiery Chinese sorghum-based spirit also known as baigan. During one drinking session with colleagues in the early 2000s, Xie joked that he should stop drinking baigan, because the name of that spirit is a homonym in Chinese for "working in vain."

Despite his laid-back charm, some former colleagues said Xie never demonstrated first-rate leadership or ambition, especially as Alibaba saw explosive e-commerce growth.

In recent months, Alibaba named Zhang Hongping as managing director of Alibaba Capital, where Xie works, while much of the investment decision-making rests with Executive Vice Chairman Joe Tsai, people familiar with the matter said.

Xie confided to friends a desire for greater autonomy in making investment decisions. He wanted to invest not just to further Alibaba's strategic interests, but also to seek pure financial returns, one longtime friend said.

In his investments for Alibaba, Xie has overseen deals for e-commerce firms as well as travel-related sites QYer.com and 117go.com, and Kuaidi, a taxi-hailing app, one friend said.

Several friends said they were not surprised to see Xie excluded from the steering committee list, with one saying he noticed Xie's personal drive appeared to wane in recent years compared to younger, more ambitious rising stars like Eddie Wu, formerly Alibaba's mobile chief and now head of corporate development.

One investment colleague speculated it was Xie's even temper and a mutual understanding forged over 15 years that make him Ma's most trusted lieutenant.

"To be honest, Simon hasn't been that hungry in recent years. He feels happy where he is," the colleague said, adding: "Whatever old Ma says, Simon listens."