LinkedIn recently eclipsed a staggering 300 million members. Over the past year since it launched, already more than two million of those members have signed onto the company’s LinkedIn for Good program to offer their skills and time to nonprofits through skills-based volunteering and board service.

Led by Meg Garlinghouse, LinkedIn for Good represents a remarkable show of strength and generosity, both on the part of LinkedIn and its members. But Garlinghouse has found herself with a surprising predicament: “Week after week, we get about 60,000 members signing up; we simply can’t work quickly enough to feed the appetite of our members,” she explains.

Though the number of nonprofits using LinkedIn for Good to connect with volunteers increased ten-fold in the second half of its launch year (to 8,000), the amount of available work falls far short of what members are ready to offer. At present, it breaks down to 250 volunteers per nonprofit.

Having directed a smaller-scale pro bono design program—The 1% program of Public Architecture—I can empathize with LinkedIn’s quandary.

Based on what amounted to a two-year pilot, focused exclusively on recruiting a few dozen design firms, my Public Architecture colleagues and I had a hunch that hundreds more firms would be willing to commit a percentage of their time to pro bono service—work ranging from conducting feasibility studies for nonprofit space improvements to the construction of actual projects. Our hunch proved correct, and we were quickly inundated with firms of all sizes.

We felt equally sure that infinitely more nonprofits would come clamoring to help those firms make good on their pledges—so sure, in fact, that we waited another two years to build up a solid base of firms before opening up the flood gates to nonprofits.

Instead of a flood, we got a trickle.

Today, The 1% program counts 1,309 design firms among its ranks—ranging from single-person to huge multinational firms. Collectively, they’ve pledged more than 400,000 hours of their time, representing an estimated $60 million in donated services annually. Meanwhile, a total of only 839 nonprofits have registered with the program over the past seven years. With an estimated 50,000 professional design firms and 1.5 million nonprofits in the United States, we expected the demand to far outweigh the supply, but it hasn’t.

Even well-intentioned programs like these risk engendering what psychologists call “learned helplessness”—the idea that when people (volunteers, in this case) “put themselves out there” at the invitation of others but find no place to direct their energies, they are less likely to offer help in the future.

So why do programs like these have such difficulty reaching or attracting organizations that need help? Because building demand is a high-touch affair; it requires significant relationship-building. These sectors are very segregated in general, so there aren’t a lot of authentic relationships between contrasting cultural boundaries. There are also considerable differences in how, when, and why nonprofits seek out services—most often when needs arise, though that’s something these programs could capitalize on.

In the service world, the Taproot Foundation and Catchafire offer compelling models to address this reality. Taproot generates competition among nonprofits  for “serve grants.” It rigorously vets applicants and pairs them with professional teams to address a very specific need (such as building a donor database or producing an annual report)—and it does so on a clear timetable. Catchafire, a for-purpose social mission business, employs a similar process and offers a parallel set of services. Garlinghouse readily acknowledges the strength of the specificity brought by these programs, but even Taproot is frequently maxed out with LinkedIn members.

What, then, might be said for high-volume models like LinkedIn for Good and The 1% program, which demonstrate an immense amount of goodwill, but struggle to build equally strong demand channels? The nonprofit social enterprise TechSoup Global may provide one answer.

With an extensive database of more than 600,000 nonprofits worldwide, TechSoup has positioned itself as a potentially game-changing connector in this space. “We’re serving more than 100,000 organizations a year, helping NGOs around the world gain access to hundreds of millions of dollars in donated technology products and services,” explains Kyle Reis, TechSoup’s senior director for Global Data Services. “Even though it gets much more complicated when we’re talking about volunteer services, we see this as an opportunity to collaborate with others working in the space to unlock a potentially enormous resource for thousands of nonprofits around the world.”

LinkedIn recently identified TechSoup as a potential partner to help build demand; it was one of half a dozen organizations to explore this supply and demand imbalance last summer. Though LinkedIn had only limited success in attracting TechSoup nonprofits to its program, Reis sees it as a solvable problem: “This is a prime opportunity to use what we call ‘community-centered design’—to develop a workable and scalable solution to what is essentially a delivery problem. There’s something missing here.”

As with TechSoup’s software distribution, Reis also sees a delicate balance between high-volume and high-touch. “We feel there’s something between these two.”

The robust supply of good intentions embodied in LinkedIn for Good, The 1% program, and other initiatives is noteworthy and highly commendable. But as throngs of people flock to these programs looking to make a difference, they need to build equally strong demand or risk losing that goodwill.