It’s always tough for a leader to know when to finally hang it up and walk away. In the Democratic presidential race, for example, John Edwards seemed to have a good sense of this (and in hindsight, perhaps for very personal reasons), while Hillary Clinton just didn’t want to take the hint.

This is just as true in the world of business, maybe more so. Everyone likes to think they’re a critical part of the operation and that they still bring a lot of value to the equation, but that’s also why it is important to be brutally honest and have the ability to read the writing on the wall.

Here are two examples of what I’m talking about: Jerry Yang and Steve Smith.

Jerry Yang is a guy you’ve probably heard of. He’s one of the founders of Yahoo, and currently, he’s the company’s CEO. Yang was coaxed back from whatever founder duties he was tending to in 2007 to become chief executive, and although it seemed like a good idea at the time, Yang has pretty much been a disaster as Yahoo’s CEO.

His biggest screw-up is how he completely and totally mishandled the possible buyout of Yahoo by Microsoft, including offering a change-of-control package to every Yahoo employee (a move that brought on both lawsuits and criticism), refusing to streamline the company’s notoriously slow decision making, and bringing in highly paid consultants to rubber-stamp layoffs the company had pretty much already decided upon.

If that wasn’t enough to convince Jerry Yang to return to the land where successful company founders go to graze on their money, maybe this will: a Bloomberg News story this week that points out how smart Microsoft looks for not closing the Yahoo takeover deal earlier this year at $47.5 billion (or $33 per share), given that Yahoo’s market value now is around $18.5 billion (or about $13.50 per share).

In other words, Yang missed an opportunity to cash in and get out—and get his shareholders out—while the getting was good. And given the current state of the financial markets, it’s highly doubtful that Microsoft or anyone else will bid anywhere close to what Yang turned down. If this isn’t a loud and clear signal that Jerry Yang should return to the land where founders don’t have to be bothered managing, I don’t know what is.

Now contrast Jerry Yang’s inability to step away with that of Steve Smith, the now-former editor of the Spokane Spokesman-Review. Smith, like so many newspaper editors in this day and age, has had to slash budget and cut staff numerous times over the past few years. This month, when he was asked to do it again, Smith said no mas. He resigned instead.

“My parting with my publisher, Stacey Cowles, was quite amicable,” Smith told National Public Radio’s On the Media program this week. “I don’t agree that these cuts are necessary at this time, but I understand and respect his decision to the contrary. And frankly, one of the reasons that I resigned is that he needs an editor who can stand up in public and say to people, ‘This paper is going to be OK.’ Actually, better than OK—leaner, easier to read, etc. And I was not in a position to carry out the publisher’s marketing strategy.”

Yes, the Spokane newspaper isn’t Yahoo or anything even remotely close to it in size and scope, but the management challenge is still the same: making smart decisions to drive the larger organization ahead. Steve Smith knew this and recognized when he had reached a point where he couldn’t be an effective leader anymore. Once he realized that, he quit.

Unfortunately in this world, there are far more Jerry Yangs (or Richard Fulds, or Bob Nardellis) than there are Steve Smiths, and it gets back to my central premise: There is a fine art in knowing when to depart. Unfortunately, it’s a talent that many talk about, but all too few can actually bring themselves to do.