As great as Iger's track record has been in the dozen years he's run Disney — and it has been superb — the company's need to push off his planned retirement is a painful reminder of why Disney has had so much trouble with succession planning over the years.

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One reason Schultz and the Starbucks board did it right is that they had done it wrong back in 2005, when they installed Jim Donald as chief executive.

Donald had come from the supermarket business, and he didn't really fit with the Starbucks culture. "What I got wrong was in not waiting to groom someone from the inside, someone who was really part of our culture," Schultz told me recently. "Instead I went outside."

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By 2007, Schultz was complaining that the company had grown too fast, and that the Starbucks brand was being "commoditized."

The following January, with the stock in free-fall, competitors like McDonald's Corp. and Dunkin' Donuts making Starbucks-like coffee drinks, and Starbucks sales hurting, Schultz and the board fired Donald and Schultz returned as CEO and began to revive his beloved company.

This time, as he began to think about stepping down, he went about it differently.

Johnson was the CEO of Juniper Networks Inc., an internet infrastructure company, when he was invited to join the Starbucks board six years ago. Over time, Schultz came to realize that Johnson had, as he put it, "the natural qualities of being very human and culturally aligned with Starbucks."

Two years ago, Schultz asked him to become president and chief operating officer. "It'll give you an opportunity to understand the company, and see if it is the right fit," he told Johnson. "And I'll support you and coach you and guide you through this process. Then we'll get the board involved, and we'll all see if the stars are aligned."

In May 2016, when Johnson and Schultz presented to the board a five-year strategy plan that the two men had written together, it was a forgone conclusion that Johnson was going to succeed Schultz.

The handoff last week surprised no one, and pleased everyone, because Schultz and the board had done it right.

Disney, of course, was once notorious for succession problems.

Remember Michael Eisner, who ran the place from 1984 to 2005? He elbowed out potential successors like Jeffrey Katzenberg. He even tried to sour Disney's directors on Iger, who had been the company president since 2000, when the board decided to give Eisner the boot and hand the job to his number two.

There is no question that Iger has had the magic touch during his tenure as CEO. (To name just one of his many smart moves: buying Pixar from Steve Jobs and then putting two Pixar executives, Edwin Catmull and John Lasseter, in charge of all of Disney Animation.)

For awhile it appeared that Iger had succession planning under control as well. He put two highly regarded executives, Thomas Staggs and Jay Resulo, in a bake-off that lasted for years. When he named Staggs chief operating officer in 2015, the bake-off appeared to be over.

Rasulo left the company, while Staggs was seen on Wall Street as the heir apparent. Staggs had spent most of his career at Disney, had successfully built the Disney theme park in Shanghai, and was well-liked by his colleagues.

With Iger intending to leave in 2018, everything seemed to have fallen in place.

But then, in April 2016, Staggs suddenly left the company.

Neither Staggs nor Iger nor anyone else at Disney has ever explained what happened. One of the most plugged-in Disney watchers in the press, James B. Stewart, wrote in the New York Times that Iger told Staggs that he "lacked the full confidence" of Iger and the board.

And with that, he was gone.

Was there really a problem with Staggs? Nobody knows. Was Iger truly disenchanted or was he pulling an Eisner, undercutting a potential successor because he didn't want to let go? No one can say.

In extending Iger's contract to 2019, the Disney board made it clear that the company doesn't have any obvious CEO candidates. Most of the potential insiders, viewing Staggs' ascension as inevitable, have left. And because Disney also has cultural quirks, bringing in an outsider has risks.

But stretching out Iger's tenure by one year is hardly a solution. It means that Disney has only two years to find and groom a successor. That's not a lot of time.

Problems the company faces — most pressing, the turmoil in the television industry that has led to steep subscriber losses at ESPN and some faltering stock performance — are not likely to be solved before Iger hands the reins to someone else.

Two years from now, Iger will be 68. If the directors don't start doing succession planning right, they're going to wind up asking him to stay on when he's 75.

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

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