As far as I know the first Apple computer was not really a computer but a box of parts that the customer had to assemble themselves. The early days of Apple is probably the best example of "building in public" because so much of it was actually just selling the dream. In any case, the opposite is infinitely worse. Too many people wasted away for years "building in private". If and when they did finally release it was to the sound of crickets. Hacking for pleasure is one thing. If you're trying to build a business then you must be always be selling and marketing.