Salespeople have had a bad reputation in Silicon Valley. Young, lean startups looked at the “consumerization of IT,” and decided that if their software was good, the product would sell itself.

To this new breed of entrepreneurs, sales teams looked inefficient and old -- a holdover from a less advanced age of business. Salespeople were the sleazy used car dealer, or the slick-haired Wall Street type, trying to convince customers to buy things they didn’t really need. But the Valley has learned to love salespeople again.

Related: How to Shift the Culture of Your Sales Process

Dropbox, which got wide notice in 2011 for claims that it didn’t need salespeople, has announced it will open an office in New York to beef up its sales team. (In fact, Dropbox was already building a high-powered sales team by late 2012). Meanwhile, tech giants young and old, including Oracle and Salesforce.com (which probably knows a thing or two about selling), have steadily expanded their sales teams to drive growing enterprise customer bases. The sales team is back in a big way.

The unsung heroes of Silicon Valley. Why are tech companies only now relearning the value of salespeople? Despite all the headlines about brilliant hackers and coding entrepreneurs, Silicon Valley owes a lot of its success to great salespeople. One of the Valley’s most iconic figures, Steve Jobs, was not an engineer but a creative visionary and master salesman, revolutionizing the way companies communicate with their customers.

While other sales leaders may play a more behind-the-scenes role, there’s no questioning the importance of sales teams as a key driver of tech companies’ growth. Today, an average of 17 percent of the workforce at top growing companies are salespeople. This includes 14.5 percent of Twitter employees, 15.7 percent of LinkedIn employees, 32 percent of Salesforce.com employees and 26 percent of Box employees, according to estimates of the companies' LinkedIn profiles.

Without the relentless work of today’s salespeople, the energies and resources that go into the creation of innovative products and services would be wasted. Cutting-edge companies recognize that salespeople are a crucial part of the digital revolution.

Sales goes back to basics. Part of the reason that sales has regained its strong reputation is that salespeople have adapted in response to business innovations. The Internet has brought on a data deluge, where customers have access to more information about products than they could ever possibly digest.

Related: How to Recruit Salespeople Who Will Deliver Dramatic Returns

While companies can increasingly leverage Facebook and other social-media platforms to connect with customers, at the end of the day, people still want to talk with a real human being. That need has been there since the beginning of time and is just as strong today.

Among the Google search results, the flood of white papers and the automated nurture campaigns, the salesperson has evolved to stand out as the most valuable resource for customers. Companies have come to realize that salespeople play a crucial role in today’s information-overloaded society. Salespeople have evolved to become thought leaders and consultants and seriously smart people who can give customers the answers they can’t find with a search engine or on a company website.

The return of sales. Companies are aggressively hiring to fill inside sales roles in New York, San Francisco, Boston and even Austin to power their growth engine, which scales not with bits and bytes but with actual smart human beings who provide value and generate revenue.

With this newfound demand for salespeople, companies are taking two approaches. First, they’re going to unconventional places to find talented employees who can be developed into fantastic salespeople. This can be a long road, but for companies that commit to it, these sales recruits can drive tremendous value.

Additionally, companies are spending billions of dollars ($12.8 billion in North America alone, to be precise) on tools and software that help accelerate the overall sales process for each salesperson. Such tools include software the helps salespeople say the right thing at the right time, or tools that help salespeople track engagement, and even tools that can predict who is more likely to buy.

They help salespeople spend more time having meaningful conversations, so they can focus on becoming the teachers, consultants and thought leaders that companies need them to be.