Three mid-level bankers in Goldman Sachs technology investment banking group in San Francisco left the bank to join Uber.

According to Reuters, the bankers are the latest to leave Wall Street banks for Silicon Valley startups. Bankers flock to Silicon Valley due to the lure of more flexible hours. While sometimes stock options and share grants also become one of the attraction.

Although Goldman did not reveal the attrition figure, but departure of many employees to startup, private firms, and other companies in recent years drive the company to make some adjustments.Earlier this month, Goldman announced a series of changes designed to help retain more junior employees at the analyst and associate level, including promoting them faster.

Although exodus of employees from big banks are not well documented, Reuters noted a series of high profile exits, such as Ruth Porat, former chief financial officer at Morgan Stanley who left to become chief financial officer at Alphabet Inc., Google parent company. another case of high profile bankers exodus to tech company was Michael Evans. He left his position as vice chairman and head of Asia at Goldman in August to become the president of China e-commerce company Alibaba Group Holding.

Uber is currently valued at $50 billion and according to Venture Beat, it is expected to have an IPO within 18 to 24 months. Uber is the biggest among unicorn, terms for private tech startup companies worth $1 billion and above that has yet to go public. For Uber as a tech company, having bankers on staff can help smooth the path to an initial public offering and other capital raisings. Prior to the three bankers, Uber has hired senior employees from Goldman, including Gautam Gupta, finance chief and Cameron Poetzscher, corporate development head.

Goldman is in the top 10 list of companies that Uber recruits from, ahead of even large technology firms like Twitter Inc., Oracle Corp and Intel Corp. Bigger source for hiring than Goldman are big tech companies, like Microsoft and Facebook.

Bankers are hired for managing business side of tech companies. Chelsea Cooper, who worked for four years at Goldman and hired at Uber in 2012 as general manager in UK operation. She is now working at recruiting firm as head of technology division. In regard to Uber recuitment policy she said, "Uber really hired from two pools: from bankers or consultants,"

New York Post made a comparison between banking and tech industry in term of compensation. A vice president of investment banking in Wall Street can get paid $500,000, including bonus. On the other hand, a mid-level corporate development employee at a technology company like Uber might earn closer to $200,000. Although bankers leaving Wall Street may have a pay cut, a work-life balance is a bigger appeal and also the opportunity for stock options.

There is an increasing number of bankers to leave banking and work in another sector. Tech company like Uber is considered as one of the promising sector for them.