Rather than charge the normal upgrade price, which in those days was $99, he was thinking of shipping a second version of Mac OS 9 that would be given away for free — but would be supported instead by advertising. The theory was that this would pull in a ton of people who didn't normally upgrade because of the price, but Apple would still generate income through the advertising. And any time an owner of the free version wanted to get rid of the advertising, he or she could simply pay for the ad-free version. Steve's team had worked out the preliminary numbers the concept seemed financially sound."
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