With all their resources and talent, why do big companies have trouble innovating? How can a Blekko exist when there is a Google? Or a Tapulous when there is an Electronic Arts?

Even more puzzling, why couldn’t Yahoo create Facebook with Yahoo 360 instead of losing out to a 20-year-old kid from Harvard? A lot of innovation comes from tiny teams with only $100,000 in the bank, or often a lot less. The reason is they don’t fear breaking the rules.

In reality, there’s a lot of innovation happening at big companies. But most of it is incremental. The focus is usually on process optimization and efficiency improvement. In order to support the rigid, crystalline structure of a large enterprise, lots of rules and procedures are implemented and enforced. These rules are “The Box.” The goal of most enterprise innovation is to get close to the edge of “The Box” without touching the lines – like a child drawing in a coloring book.

A startup innovator doesn’t care about rules. He doesn’t care about “The Box.”  His motivation is to achieve something that has never been done. Most innovators we meet have an explicit goal of changing the world.

Another key reason why big companies aren’t good at qualitative innovation is a combination of legacy and Wall Street pressure. Most large companies do not grow very fast. Their current customer base is large, and, by comparison, the inflow of new customers is small. This imbalance creates a disincentive to introduce change and innovate. Customers often react negatively to change over the short term, and Wall Street punishes companies for taking risks.

Startups, on the other hand, are unencumbered. There’s no aversion to risk.  There’s nothing to protect.

Victor (pictured above) has seen this at RingCentral. For years, the RingCentral team has pushed the envelope with cloud telephony in an old-fashioned, highly competitive telecom industry dominated by huge incumbents. It would have been easy for RingCentral to start looking over its shoulder, and then stumble and fall. But the company kept swimming upstream, winning one innovation award after another (including the prestigious World Economic Forum’s Technology Pioneer Award) and adding more loyal customers. Now, the company is enjoying industry-wide acceptance and many of the industry’s largest names have become valued partners and strategic investors.

Ben (pictured left) saw this same dynamic as he offered advice to the Tapulous and Mesmo teams competing against the major game studios. Tapulous, for example, built out a massive network of freemium users in the same gaming market that created billion dollar businesses with Harmonix Music Systems’ Rock Band and Activision’s Guitar Hero. Neither franchise was able to embrace the iPhone as the new gaming platform, or freemium as the new business model, the way Tapulous did.

Only a few big company executives and boards have the guts to resist the pressures from shareholders and Wall Street. One example of a company that did is Charles Schwab under then CEO David Pottruck. Pottruck’s big bet was to see the Internet as the future. In the late ‘90s, Schwab offered a discount brokerage service at $80 per trade and an e.Schwab platform with reduced service levels at $64 per trade. E*Trade wasn’t yet a strong competitor. That changed.

Pottruck’s bold decision was to face rising Internet competition head-on and offer all customers, online and off line, the same service levels and the same reduced price – $29.95 per trade. This bold innovation cost the company about $100 million in profit the first year, and Wall Street punished the decision. Shares dropped by about 40%. But Pottruck and Schwab were right and within nine months the stock recovered and reached new highs on massive customer growth. Some of its competitors’ product strategies were a year behind. Stories like this are few and far between.

The startup environment is different on a fundamental economic level, not just because founders are more motivated and focused, but because anytime a startup does something big, the upside is uncapped and the downside is pretty small. If a company fails, an investor loses a few million dollars. The team goes on to get new jobs.

Big companies can look at the same project with the same economics and lose a billion dollars in market cap. Netflix is an example. The risk paradigm is reversed. For any qualitative innovation, a big company has an uncapped downside and a finite upside.

That’s why startups do what they do. They have nothing to lose, only upside. It is why they are willing to change the world.

(Victor Belfor is an entrepreneur and investor and currently runs strategic alliances at RingCentral. He can be found on Twitter @vbelfor. Ben T. Smith IV is a serial entrepreneur and investor and the co-founder of MerchantCircle and Spoke. He is available on Twitter @bentsmithfour)