Office has been the leading force in this market for a long, long time. Past competitors, including WordStar and WordPerfect, did not transition well from DOS to Windows and soon dropped by the wayside as Office became the dominant force in the industry.
Today we see new competitors in the market, particularly in the form of Web-based productivity suites such as Google Docs and Zoho. Notably, however, although both of these products are available for use free of charge, neither is open source. Most of the other traditional desktop software suits that have appeared over time, such as SoftMaker Office, have been proprietary software, too.
Even LibreOffice began life as proprietary, commercial software. It was originally developed as StarOffice by a company called StarDivision, which was acquired by Sun Microsystems in 1999. Sun open sourced the StarOffice code as OpenOffice.org in 2000. Even then, however, Sun supported OpenOffice.org development by offering a proprietary, commercial fork of the suite under the StarOffice brand.
There are other open source competitors available, including the AbiWord word processor, the Gnu Calc spreadsheet, and the KOffice suite. Even among Linux users, however, none of these projects has a user base that can compare with that of OpenOffice.org. And none of the Office competitors -- whether Web-based or desktop software -- even remotely approaches Microsoft's installed base, which consistently hovers at upward of 90 percent of the market.
You don't charge me, I won't call you
What makes it so hard to create successful desktop applications using an open source development model? One obvious problem is the business model -- or lack thereof.
Most of the prominent, successful open source software caters mainly to the data center and developer markets. The Apache Web server, the MySQL and PostgreSQL databases, Eclipse, Perl, Python, Ruby, and (arguably) Linux itself are just a few examples. Most of Sun's software portfolio -- the bulk of which was available under an open source license -- fell under the same category.
Some of these projects are largely volunteer efforts -- the programming languages in particular. Of those that do make money, however, most use a commercial support model. Enterprise customers who rely on open source software for mission-critical applications are willing to pay hefty license fees for the ability to gain knowledgeable product support with a simple phone call.