A commenter on one of my articles recently asked: "Why is it that true believers feel the need to replace every last proprietary app?" He continued: "VMware, Skype, and Google Earth are best-of-breed and free-as-in-beer."
Over the last year or two, such sentiments -- often rudely expressed -- have become increasingly common in the free and open source software (FOSS) community. But, when you think for a while, they miss the point. If free software is to achieve its goal of guaranteeing that users can control their computing, then a completely free operating system is a basic necessity. An almost completely free operating system is both short-sighted and not enough to give users the control of their own computers that is supposed to be FOSS's ultimate goal.
In one sense, the idea that all we need is a mostly free operating system is a direct indication of where FOSS is today. Most types of software needed for productivity and leisure computing are now available as FOSS applications, and those that aren't, such as Flash, or video or wireless drivers, are available as free downloads with proprietary licenses. This state of affairs means that, if you don't care about licenses, for the last few years you have been able to run most GNU/Linux distributions without any inconvenience. After so many years when running GNU/Linux meant giving up some functionality, you can perhaps understand why users might be so relieved that the situation has changed, even if it is not ideal.
However, this attitude is only defensible from certain points of view. If you are in the open source part of the community, then your interest in free software is that it allows the development of better software more quickly. But if a proprietary piece of software is already "best-of-breed," then why should you bother developing a FOSS equivalent? From this perspective, the logical course is to use the superior software, regardless of the license.
Similarly, if your interest in GNU/Linux ends with it being available gratis -- "free-as-in-beer" -- then you are unlikely to care about free licenses. If software is available at no cost, but has a restricted license, then you will undoubtedly welcome it with the same enthusiasm as anything released under the GNU General Public License.
The most obvious trouble with these viewpoints is that they are short-sighted, even in their own terms. The idea that focusing on quality and ignoring licenses is the best policy is disproved by the well-known story of how Linus Torvalds chose BitKeeper, and pieces of proprietary versioning software for kernel development, only to have to scramble for a replacement when the free version suddenly became unavailable. The same vulnerability is present in software that is simply gratis. The fact that a change in license hasn't happened yet with a particular piece of software is no guarantee that it won't.
After all, according to the typical proprietary end-user license agreement, you do not own the software -- you are simply allowed to use it under the terms the company chooses to offer.
Moreover, should the manufacturer discontinue the software, your only recourse is to keep using it until updates to your system make it unusable. That was what happened to Apple users of Internet Explorer. The fact that users got a better default browser in Safari was purely accidental; that was not Microsoft's intention, and they were still inconvenienced.
By contrast, when you use free software, such problems do not exist. Under the terms of the GNU General Public License, the most popular FOSS license, the distributor cannot change the licensing terms on you, and, should development on the software stop, you or someone else -- perhaps someone you hire -- can start it up again. Although free software licenses do not talk about ownership, in effect, that is what they give you, subject to very nominal requirements to preserve notices of authorship and the license should you redistribute the software. These restrictions are so mild and so easy to meet that most users are unaware of them and fulfill them without any special effort.
However, insisting that free software continue on to its logical end is not just a matter of short-term convenience. It is also the only way to guarantee that you control your computer. Manufacturers of proprietary software often worry about whether using FOSS will affect their products, but the reverse is also true: the right piece of proprietary software can affect an otherwise free system. For instance, should a proprietary video driver be withdrawn, perhaps because it is for an older card, then you might lose the ability to take advantage of 3-D acceleration, or even to use graphics at all. On a lesser scale, you might lose your ability to run certain programs, or to use certain formats.