Google's so-called bench of veteran executives and engineers is deep and packed with familiar faces, and it's no accident.

The internet company's obsession with prized engineers and product gurus, and its competitive instinct to keep them away from rivals, mean certain executives can essentially rotate out of an active role for months or even years at a time, often getting paid to wait until the organization needs them again.

Some of those veteran faces return to the spotlight. Omid Kordestani, Google's first sales boss, was called back to active duty last year to oversee the business after the abrupt departure of chief business officer Nikesh Arora.

Brian McClendon, one of the early forces responsible for the popular maps product, has been in a quiet limbo for more than six months after leaving his post at the helm of the maps team last fall. McClendon is a "towering figure" within Google but is "on the bench" as he figures out his next move, people close to the company say, though it is unclear whether he will start a new project at Google or leave the company entirely.

Meanwhile, Salar Kamangar, one of Google's first 15 employees and the former head of YouTube, technically has the title of senior vice president of products, though his actual role now involves advising CEO Larry Page, according to a recent report from The Information.

The bench system is an effective but little-discussed strategic tactic in Google's playbook as the company looks to expand into new markets and keep an edge over a growing crop of web challengers that are all desperate for seasoned internet business experts.

"It helps keep people off the market," one former Google executive says. "It helps keep the institutional knowledge if you need them back for any reason. And it costs [Google] so little to retain these people rather than to have them leave and start the next Facebook."

About one-third of Google's first 100 hires still work at the company, according to "Work Rules!" a recent book by HR boss Laszlo Bock.

It's more of an informal system than an established program, sources say. But the underlying intention and goals are clear and purposeful. "It's very rational," the former Google executive says. (Google declined to comment on this story.)

With its deep pockets and sundry internal projects, Google can offer its elites attractive incentives to hang around, even after they have moved on from, or been replaced in, their previous role. The company will often tell someone to take 18 months or 24 months to figure out what he or she wants to do next at the company, the former Googler says.

In case of emergency

In some cases valued execs are given general titles like "special adviser." In other cases they are tucked into various parts of the company, often in roles that are not clearly defined or of obvious strategic importance.

It's not unusual for high-level executives to suddenly "go dark," another former Google employee said, noting the various confidential projects that are always percolating throughout the company. Jeff Huber, who once oversaw the commerce and geo groups, now works in the Google X labs, toiling on undisclosed projects. Mike Cassidy, who came to Google in 2010 when the team that built the Ruba travel site was acquired, ran Google's internet balloon initiative in secret for a year before Google announced it in 2013.

Some executives are biding their time, waiting for the next interesting opportunity to open up within the company, another source said. Others are more like emergency assets stored inside a glass case, which can be shattered in a pinch. Jonathan Rosenberg has had various roles since stepping down as head of product in 2011. Google

When Jonathan Rosenberg stepped down from his role as head of product in 2011, many insiders and outsiders assumed he had left the company for good. In fact, he remained on the Google payroll, retaining his office and administrative assistant, according to people with knowledge of the matter.

Rosenberg acted as a behind-the-scenes adviser to the team leading Motorola after Google acquired the cellphone maker in 2012. When Motorola CEO Dennis Woodside resigned and took a job at Dropbox in 2014, Google quickly called on Rosenberg to fill the breach, giving the old-hand oversight of day-to-day management and providing continuity.

Rosenberg's latest assignment is to lead Google's robotics team, apparently on a temporary basis, after a succession of management changes in the group, according to the Information report.

The 'Larry translator'

Google initially used the title "special projects" for some of these roles but later settled on "adviser," another former Google manager says.

Special projects seemed to connote that the person was starting new business, which could cause internal confusion or create political conflicts within the organization. Adviser is much more innocuous and denotes a supporting role, the person said.

The bench system isn't reserved for high-level executives. Valued rank-and-file engineers or business-side employees can also rotate out of active duty, another former Google employee says, recalling one colleague who took six to eight months to figure out his next move, all while getting paid.

In some cases an employee on the bench continues to do some work on his or her main job; other times employees can unplug more completely. Fourteen-year Google vet and head of web spam prevention Matt Cutts announced he would go on leave last summer and has extended his time off into 2015 (though it is unclear whether he is still on the payroll).

The ability to get paid and continue vesting stock while figuring out life's next steps has an obvious appeal. And the stature and credibility that the elite programmers and executives enjoy within Google is not easy to part with.

"Google is a very intense place. They realize that everybody at some point burns out and needs to take a break," the person said, citing the system as an important benefit at Google. "How many places can afford to pay people full salaries if they're not doing a full-time job?" The one who got away: Andy Rubin left Google after 10 years. AP

Not everyone sticks around permanently, though. Andy Rubin, who led the creation of Google's successful Android mobile software, left his post in 2013 to create a new robotics initiative within Google. But after nearly 10 years, Rubin ultimately left Google in October to create an incubator for independent hardware start-ups.

For Google, the value of keeping a collection of proven executives may be best illustrated by Kamangar. Having served as the head of YouTube and been credited with creating Google's first business plan, Kamangar knows everything about the company, and more importantly, about its mercurial cofounder and CEO Larry Page.

He is a Larry Page "translator," the former Google executive says. He noted that Kamangar could practically predict what Page would say in certain situations and was ideally suited to function as a liaison between Page and the organization.

"Larry will challenge everything, but he will listen to Salar's arguments with a lot more weight," the person said.

Several other former employees echoed that idea, saying Page "really trusts" Kamangar.

If a certain product group is planning to present something to Page, Kamangar can help prepare them, advising them on the best approach to take. That way the team is less likely to be shot down by Page and become demoralized.

"When you're Larry, you need like 15 of these people."