By Andy Boynton with William Bole, Special to Portfolio.com

Most innovators would know exactly what Thomas Edison meant when he said that if you want one good idea, you have to come up with many ideas.

David Kelley, founder of the celebrated product design firm IDEO, has fleshed out this point in making the case for quantity. “If you’re forced to come up with 10 things, it’s the clichéd things that you have off the top of your head. But if you have to come up with 100, it forces you to go beyond [the trite notions],” he observes.

In other words, in the early stages of a project or innovation, the more ideas the better. This is a rule worth following, but in the end, you’ll probably have an oversize load of ideas. At a certain point, you’ll need to start making decisions about those ideas, and some of those decisions will be tough.

Robert Sutton, a professor of engineering and management science at Stanford University, tells of a visit that Steve Jobs paid to Yahoo headquarters in Sunnydale, California, some years ago after the top brass (one of whom funneled this account to Sutton) invited him in for a talk.

During the meeting, they came around to the subject of bad ideas and the task of purging them. That’s no sweat, Jobs told the Yahoo leaders, adding that almost anyone can do that. The hard part, he stressed, is killing off good ideas—which must be done.

His point was that any successful idea requires a vast amount of attention (read: resources), and there are only so many ideas that can get this sort of treatment. Many good ones will have to go.

But how do you part ways with ideas that may seem promising and worthwhile? To begin with, one thing to keep in mind is that an idea may be good for others, but not quite right for you. All ideas need to be considered in light of your gig—what you’re all about as a professional and where you want to be going in your career.

There are some basic questions that you could ask yourself: Do I enjoy spending time and energy on this initiative? Deep down, do I really want to be involved in this project? Do I want to be known as the person who brought this idea to life?

Deliberately or otherwise, you might have already done this sort of screening. In that case, the immediate task is to start prototyping—getting your ideas into some rough form. There’s no better way of winnowing down the ideas that seem right for you but still need to be gotten rid of.

It helps to have a method. Walt Disney and his team liked to use storyboards, which started out as sheets of paper with rough sketches of movie scenes pinned up on bulletin boards. He used a storyboard when prototyping ideas about what people might want to see in a theme park—what kinds of rides, whether there should be trains, and so forth.

As a Disney associate recalled years later, “We would just…put up our ideas…and he’d come down in the afternoon and sit there and look at them and juggle them around.

And eventually it evolved”—into Disneyland.

At L.L. Bean, product development teams have an elaborate way of prototyping ideas for the purposes of choosing from among them. They splatter a wall with sticky notes—hundreds of them—each one articulating a product requirement (an idea). Then the teams begin trimming down the list of requirements, which are based on extensive interviews with customers. They do so by voting. Why not? They’re a team, and the members need to begin working collaboratively with a leaner list of ideas.

After several rounds of voting, the teams organize the requirements into clusters. At the end of a three-day ritual, in a secluded environment away from corporate offices, they have a poster displaying a final list of product requirements.

The general takeaway is that: There’s value in capturing all the ideas, in a form that’s viewable; and there are ways of getting the ideas down to a manageable few. Whatever the approach, the key is to make the ideas visible—and start killing them off.

The big caveat here is that our old and unused ideas can be valuable resources. The good ones need to be stored somewhere, not eliminated once and for all. But Jobs was right. At some point, good ideas need to be ejected from an innovation process or they’ll start mucking it up. Worse yet, they’ll end up in a final product that’s poorly defined and tries to do too much.

By all means, get the ideas flowing, lots of them. But then give some serious thought to how and when you’re going to shelve many of the good ones.

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