Given that someone already wrote something (scratching their own itch, hoped to make money but gave up, altruism), they may decide to jump from low adoption+rec

Given that someone already wrote something (scratching their own itch, hoped to make money but gave up, altruism), they may decide to jump from low adoption+recognition to potential ubiquity by releasing the software free for others to exploit. On the basis of individual incentive alone, this is inevitable.