"For the first time, he had a big financial base behind him," said Tohme R. Tohme, an orthopedic surgeon-turned-businessman who was once Jackson's spokesman and confidant.
Mottola suggested that the demands of preparing for the tour might have been too much.
"It's not just another big act going out on the road," he said. "Michael always had to surpass, always wanted to top what he'd done last."
AEG Live billed the sold-out "This Is It" concert series as the most expensive and technologically advanced arena show ever. AEG had invested more than $20 million to mount a production that was to have included up to 22 sets, elaborate light shows and high-wire acts.
The company, which owns Staples Center and other venues, had also set aside 50 nights at the O2 Arena, its European showplace.
With Jackson's death, AEG will have to refund the $85 million worth of tickets that were sold. Gone are the company's expected profits -- an estimated $115 million, according to Billboard -- as well as plans for a global three-year tour that the company had predicted would gross $450 million.
"They are taking a big hit," said Gary Bongiovanni, editor of concert-tracking publication Pollstar.
Among the company's priorities, he said, will be trying to find other acts to fill the O2, a 20,000-seat arena that does not rely on resident sports teams to fill its seats. Jackson's concerts were scheduled to run through March.
"They will be able to re-book some of those shows. But those in July, the building will probably be dark. You have an empty building, and that's going to have an impact on their London operations, certainly," Bongiovanni said.
AEG struggled to get affordable insurance for the shows, given Jackson's history of canceling tours and his 12-year hiatus from performing.
Phillips vowed to self-insure the shows if carriers wouldn't, and ultimately the company secured coverage for what Phillips called "the first $23 million."
Mary Craig Calkins, a Los Angeles lawyer who specializes in insurance issues, said many entertainment companies get several kinds of policies before a big tour, including one that specifically covers the health of the star or "key man."
"Usually, they would put in place a package that would have multiple aspects to it. If you are headlining Michael Jackson, you have to have Michael Jackson at the show, so we would expect they would have a policy that would cover if he got laryngitis or had a minor traffic accident or died," she said.
AEG officials declined to comment.
"We're dealing with a tragedy. We have no comment on that," a spokesman said.
In an interview last month, Phillips said that when the company announced the Jackson comeback, he was derided by colleagues in the industry.
"Everyone was very unsupportive. . . . You know, 'He'll never do it. You're fooling yourself.' All of that," he said.
Phillips said he persevered, convinced by the physical exam showing Jackson was in good health, a contract that bound the singer to show up and a conviction that "in this business, if you don't take risks you don't achieve greatness."
AEG had produced other "concert residencies" for singers, including Celine Dion and Prince, but Phillips had hoped Jackson's performances would cement the company's reputation among artists.
AEG Live is a unit of Anschutz Entertainment Group, which is owned by Colorado billionaire Philip Anschutz.
Those close to Jackson said they could only hope that his troubles would not overshadow the import of his musical career.
"It's a tragic end to someone who contributed so much and touched us all, hopefully someone whose final years will be remembered for more than his legal woes," said Scott Ross, an investigator on Jackson's legal defense team.
Times staff writers Carla Hall, Richard Winton, Ari B. Bloomekatz, Molly Hennessy-Fiske, Anna Gorman, Raja Abdulrahim, Yvonne Villareal, Rosie Mestel and Hector Becerra contributed to this report.