John Chambers announced recently that he'd stay on at Cisco for another three to five years, and Charlie Giancarlo departed. Cisco now seems back where it started with respect to a Chambers successor. Clearly every company that expects to last more than a couple of decades needs a succession strategy for its top position, but just as clearly there are real problems coming up with one. Cisco's not the first tech company to have a charismatic and possibly impossible-to-follow leader. Leaders with strong personalities have sometimes fared well, sometimes badly.

Ken Olsen at Digital Equipment Corporation was perhaps one of the giant figures of the 1970s, a man who had taken DEC from essentially nothing to the No. 2 computer company. People seriously talked about DEC minicomputers knocking off IBM mainframes, making DEC the No. 1 tech company in the world. Olsen was no shrinking violet with the media and customers, and he was also someone with strong opinions. It was those opinions that got him into trouble.

Olsen believed in the proprietary. Back in the 1980s he described Unix (the predecessor to today's famous Linux) as “snake oil.” Earlier he made perhaps his most telling error. “There's no reason for any individual to have a computer in his home” is perhaps vintage Olsen. These two statements encapsulated the mistakes that ended up with DEC sold to a personal computer company (Compaq), which was ultimately sold to DEC's smaller competitor, HP.

Then there's Apple. It was started by Steve Jobs and friends Steve Wosniak and Ronald Wayne, but it's Jobs who has come to epitomize Apple. He is highly charismatic, occasionally highly arrogant and always entertaining to the media. His tenure at Apple was interrupted after he clashed with his designated successor, John Scully, and he went on to found Next Computers. But Scully and his successor couldn't make Apple strong, and Jobs came back in 1997. Since then, Apple has been a tech powerhouse.

Jobs illustrates an important point, especially when contrasted with Olsen. It's OK to be charismatic, even arrogant, as long as you don't make any mistakes. An organization with a strong leader can do great things fast as long as the leader's right about everything, but it doesn't do well when that leader commits a major blunder.