This article originally appeared on HBR.org (subscription may be required).

When it comes to investments, here’s a general truth: the larger a company gets, the smaller it thinks. The process is insidious, and companies must always be on the lookout for signs that it is setting in. If you want your business to grow sustainably at scale, you need to figure out how to make big investments that will best differentiate you in your core.

We were reminded of this a few years ago, when we studied a major European conglomerate with more than 50 distinct businesses spread across dozens of markets. The company had experienced no organic growth in over a decade, the stock price had melted away and it was seeking growth in all the wrong places. We soon figured out why.

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First, the growth of most of its acquisitions had actually slowed after being acquired—the opposite of the justification for their purchase. Second, the company’s capital was spread uniformly across an extraordinary range of business types and competitive positions. The company was making big bets on its acquisitions, but it had many companies in the family and treated them all equally. It invested in its bad businesses hoping that they would become more like the good ones, and it didn’t invest massively in the good ones, because they were doing fine.

The result? Consistent mediocrity.

The best companies—those that grow sustainably and profitably at scale—reject that kind of “peanut butter” approach of spreading resources around as evenly as possible. Instead they’re “spiky” in how they allocate funds and they invest big in three areas: game-changing capabilities, next-generation leaders, and next generation business models:

They use the power of 10X—a willingness to commit 10 times the normal resources—on their critical capabilities. Amazon, for example, has learned that same-day delivery could increase revenues significantly, and it is also aware that new insurgent start-ups such as Instacart and WunWun are focusing on the instant delivery of certain products, so it has invested in its own delivery fleet, drone technology and more.

Mukesh Ambani, the wealthiest man in India, thinks the same way—and in doing so, he has made Reliance Industries, a Mumbai-based industrial giant, the most valuable company in his country. In 2000, Ambani thought big about critical capabilities for the future core of his business and built an integrated petrochemical complex designed to serve a full 25% of the giant Indian market, with technology and scale that gave it a 30% cost advantage over his regional competitors. Most companies would have backed off from such an investment.

The bottom line: Great leaders fight entropy and are willing to step up to a 10X decision to invest in game-changing capabilities.

They invest massively in next-generation leaders. That’s one of the great secrets to the success of AB InBev, the world’s largest beer company. “Talent management is easily over a third of all executive time when you count it all,” one long-standing company employee told us about how the company is run. “It is big.” He went on to describe talent management as especially important because of the uncommonly large jobs and aggressive targets that AB InBev gives its employees very early in their careers. “The first time you come in,” he said, “you get a hugely difficult target, and we watch for the reaction. You get lots of coaching and guidance, but if you don’t embrace challenge, that is a sign. The key element in all of this is how to apply the meritocracy. Everyone talks about it, but our whole system is built on meritocracy. It is why our investment in young talent is so high.”

Olam International, an enormously successful agribusiness, has leveraged the power of this approach to great effect. Sunny Verghese, the company’s CEO and cofounder, directly involves himself in all promotions of his top 800 employees, each of whom he knows by name and has an opinion about. Until recently, he insisted on interviewing all hires from the outside—in a company of 23,000 people.

We could go on. But instead we’ll just make a simple observation: Great leaders invest a huge amount of their time in recruiting, mentoring, promoting and trying to retain the best people. They recognize that aggressive meritocracy is the best way to grow sustainably. Whenever possible, they even work to generate mini-founder opportunities within their companies, to foster responsibility and leadership experiences for their most talented people. We have never met great leaders who feel they have overinvested in talent.

They invest in their next-generation business model and in the specific capabilities that will differentiate it. That’s what Sunny Verghese has done with Olam. From its modest beginnings in 1989, the company has expanded to 45 commodities in 65 countries, reaching a level of $13.6 billion in annual revenues and more than $650 million in profits. The company’s success has made it one of the best-performing IPOs in Asia in the last decade. The company’s performance is all the more amazing given the low growth of its markets, the practical challenges of building secure supply chains in places like Nigeria and the inherent complexity of the business.

How did Verghese do it? He recognized an opportunity and invested big in the capabilities that would allow him to seize it. Before Olam, the typical cashew farmer would sell his crop to a local intermediary, who would then sell the shipment to a distributor, who would then hire someone else to transport the product to warehouses where large global companies would collect it. No one “owned” the full supply chain, and as a result it was leaky, unreliable, hard to trace and rife with corruption. Farmers received only a tiny fraction of what they were entitled to.

Verghese and his team believed that they could differentiate the company to global customers like Nestlé by focusing on the end-to-end supply chain, with the goal of managing the whole thing themselves. So they went after that goal, investing in a big way, and today they have the only supply chain in their key markets that is completely controlled from the farm gate to the end user.

Examples like the ones above show that companies can and should continue to “think big” even as they grow. These are hard decisions for leaders to make, but the great ones overinvest on the few critical capabilities and assets that will drive the future business and resist the temptation to treat all their businesses the same.

Chris Zook is a partner in Bain & Company’s Boston office and has been a co-head of the firm’s global strategy practice for twenty years. He is a co-author of a number of bestselling books including Profit from the Core and The Founder’s Mentality: How to Overcome the Predictable Crises of Growth (Harvard Business Review Press, June 2016).