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From now defunct blog:
Business is business, and business loves proprietary patented technology with its pseudo monopolies used to leverage revenue and increase value. These kind of leverage points used to drive income are noticeably missing in the open source model. Instead, businesses focusing on open source tend to use the services model for revenue. It makes a lot of business sense to use open source software in your business, but it doesn’t make much sense to produce open source software in your business.
I meant to write about impossibility of making money writing open source but this guy was there first.