Retired 2004, returned 2007
Dell founder and CEO Michael Dell
Twenty years after he founded the company in his dorm room, Michael Dell ceded control to Kevin Rollins, a former Bain partner. Under Rollins' watch, the company faced a slew of challenges: customer service complaints, growing competition from HP, and an SEC investigation into its accounting. When Rollins resigned in 2007, Dell returned to attempt a turnaround.
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