DocuSign shares plunged 12% on Friday even though the electronic signature company had just reported better-than-expected earnings. The problem had to do with challenges the company is having pulling in additional revenue from customers.

It's become a familiar theme among cloud software companies in recent weeks. Longer sales cycles and difficulty in sales execution were themes that popped up in earnings calls from Box, Zuora, Cloudera and Pivotal Software as well. All of them got punished by Wall Street, some much more than others.

In part, they're dealing with the growing pains that come with being maturing companies and the complexities of dealing with large enterprises while at the same time trying to meet the demands of public market investors.

For DocuSign, the issue stemmed from the $220 million purchase last year of SpringCM, which took the company beyond a single product for digitally signing documents and into an area called contract lifecycle management (CLM), which involves managing the creation of documents for people to sign and then keeping track of changes.

"By becoming a two-product company, in the short run, it's harder to sell," DocuSign CEO Dan Springer told CNBC in an interview on Thursday before the company announced earnings. "You elongate the sales cycle. You put a short-term dampening, I think, on your billings, but you increase your long-term billings, because we have more to sell."

Springer elaborated on the financial implications of DocuSign's expansion during a conference call with analysts, who were asking about the trend. He used a European bank as an example.

"Normally, we would have had a more straightforward e-signature only," said Springer, who was previously CEO of marketing software company Responsys, which Oracle acquired for $1.5 billion in 2014. "They were interested in also looking at some of the CLM capabilities of SpringCM. And as we got to the sort of end of the quarter, we realized our normal sort of pacing and process would take longer. And it's a deal that closed 10 days after the end of the quarter."

Prior to this week's earnings report, DocuSign's stock price was up 89 percent from the company's IPO last year. It's part of a crop of subscription cloud-based software companies that have gone public in recent years and provided growth stories to enterprise technology investors.