With today's announcement that Chuck Robbins will succeed John Chambers as Cisco CEO, we had to wonder — why Robbins?

After a 16-month evaluation, the board unanimously approved Robbins on May 1. He isn't coming from out of nowhere; he's been at Cisco since 1997 and has been responsible for Cisco's sales team. But many thought President of Development and Sales Rob Lloyd would be the next to take the reins, and COO Gary Moore was considered a favorite as well.

Christian Renaud, senior analyst at 451 Research, says that Robbins wouldn't have been his first bet, either, but Robbins comes from a sales background, much like Chambers. Not only does it go a long way toward easing investors' stress, but it's also hard to deny the impact of billions of dollars in profit that came from Robbins' sales experience, Renaud says.

Another factor that bodes well for Robbins' appointment is his deep understanding of channel partners. The channel is a challenge, and with Robbins, Cisco gets someone at the helm who has a good grasp of partner relationships and ecosystems, says Brad Casemore, an analyst with IDC.

While this undoubtedly played a part in the board's decision, Casemore also notes Robbins' emphasis on operational rigor. This means a tight ship in Cisco's future, even more so than what Chambers brought to the CEO chair, something that may have piqued the board's interest in Robbins.

Moreover, Robbins is known for doing things in an economical and exacting manner, which could lead to Cisco taking a new approach to the market, Casemore says.

“The board very quickly closed ranks and found a lineman in Chuck Robbins as the leading candidate," says Casemore. "All candidates had an opportunity to present to the board and show where and how they wanted to take the company into the future. Chuck presented the most compelling vision for Cisco’s future.”

Despite his qualifications, unifying the Cisco executive team will pose a challenge for Robbins. The good news is that Chambers left Robbins with a group of extremely well-versed product people, like Mario Mazzola (leader of three Cisco spin-in acquisitions, including Insieme), who can help him get up to speed in this space, Renaud says.

Still, with new blood in charge, it's no surprise if some feel slighted by the decision and opt to move on from Cisco.

It's happened before. In 2007, when Chambers said he wouldn't be leaving his post, two executives presumed to be internal CEO candidates waved goodbye. In February, senior executive Mike Volpi left, and in December, Charles Giancarlo exited as well. It's safe to say something similar is probable after today's announcement.

"John has a bunch of credibility and charisma with customers and clients, and you want that continuity," says Renaud on Chambers' continued involvement as executive chairman. "John will continue to be involved in order to assuage customer and investor fears, but over time you won’t hear a lot about John. His amount of mentions will diminish as Chuck ascends into his own."

People have long awaited Chambers' departure, even before his 2012 proclamation that his stepping down was imminent in two to four years. Three years later, some people had started asking, "Why hasn't he left yet?"

Chambers' 20-year reign as CEO is almost unprecedented in the tech world, and his successes cannot be ignored. Cisco has had its fair share of threats during his tenure, but it was important that Chambers stick around to put Cisco in a defensible position prior to his retirement, says Casemore.

"I can't think of a time in Cisco's history where they haven't been at war," says Renaud. "There is never a time that is better or worse, because there will always be drama."

"The threats are by no means gone, but now is a good time to transition," Casemore says.