Ideally, succession planning should begin the day the ceo starts, says Claudia Allen of kpmg, a consultancy. That involves building a pipeline of candidates, assessing their skills and developing a plan to fill gaps. Public spectacles like the six-year saga to replace Jack Welch at ge, a once-mighty American industrial giant, are best avoided. Separating the roles of chief executive and chairman of the board can help, too (appointing a lead independent director is seldom sufficient to keep in check an almighty boss with both jobs, let alone sack one). Two in three s&p 500 ceos who have been in the role for longer than a decade also chair the board, compared with two in five for the whole group.

Perhaps the most important rule for succession is to make a clean break. Bosses that hang around after their turn has ended do their successors a disservice. The most pernicious example of this is the ceo who stays on as “executive chairman”, a loosely defined title that gives its bearer the right to meddle in big decisions while shirking operational responsibility. James Gorman of Morgan Stanley will take on the title when he steps down as the bank’s ceo in the coming months.

Last year 15% of s&p 500 companies were presided over by an executive chairman. Some, like Jeff Bezos and Rupert Murdoch, are founders eager to maintain a say over the companies they built. For the rest, the role may look like a handy way to smooth a transition. But it brings dangers. Predecessors may struggle to accept shifts in strategy, and confusion may reign as to who is ultimately in charge. During Mr Iger’s stint as executive chairman of Disney, he and Mr Chapek clashed over a number of big decisions, denting the new hand’s credibility.

Get an afterlife
That ceos find it hard to let go is unsurprising, and not only because power is seductive. Many struggle with the sense that, having reached their professional pinnacle, there is little left to do, says Mr George. Rather than retiring to a life of leisure, he counsels bosses to find ways to make use of their wisdom. Some may choose to sit on boards. Others, like him, may teach. Others still may try their hand at politics. Before his latest return to Starbucks Mr Schultz toyed with a presidential bid; Mr Dimon is being urged by some to pursue one. It is uncomfortable to accept that an organisation you lead will survive without you. But stepping down need not mean stepping into obscurity. Many of America’s bosses still have plenty to give—not least a shot for the next generation.