"In 2001, I wrote a report that said, 'Don't touch it.' In 2004, I wrote the same thing. It wasn't until 2007 that I said, 'It's good enough,' " Sampson said.
Despite the zig-zagging, SharePoint grew quickly. A year and a half after the release of SharePoint Portal Services, the software had 7 million users.
Two years later, the software, now called Windows SharePoint Services (WSS), had more than quadrupled to 30 million users in January 2005.
Eighteen months later, that number more than doubled again to 75 million users, by which time the software had a new name, Microsoft Office SharePoint Server (MOSS), with WSS kept only for the free version.
Bundling pays off
One constant is that since 2001, Microsoft has bundled SharePoint's Client Access License (CAL) as part of its Core CAL Suite, said Paul DeGroot, a licensing analyst at independent firm Directions on Microsoft.
CALs are licenses that Microsoft requires companies to buy for desktop users of a server application.
"Even though a lot of customers didn't know what SharePoint was at the time, they bought the Core CAL Suite because it included CALs for Windows and Exchange, which they did use, and Systems Management Server [now called System Center Configuration Manager], which a few more used," DeGroot said.
"So there's no question that in the early days, SharePoint's 'momentum' was illusory. Many people were getting the Core CAL, and almost accidentally getting SharePoint CALs," he said.
Those buyers of SharePoint never deploy the software, turning it into shelfware. "There are no doubt a lot of SharePoint licenses that are, at minimum, underused," DeGroot said.
Sampson wrote a widely read blog post in March 2008 decrying Microsoft's announcement of its 100 million users and its $1 billion revenue figure.
"Licensed users does not equal real users," he said, estimating that the percentage of SharePoint licensees actually using the software is "more than 40% but less than 70%."
It could be even lower. An IDC poll of 262 enterprise IT managers published this month found that an average of 22% of corporate employees were actively using SharePoint.