As others pointed out, nobody else mentioned sale by public offering. But let's go with it anyway, why is that different? It's just a way to have multiple owne

As others pointed out, nobody else mentioned sale by public offering. But let's go with it anyway, why is that different? It's just a way to have multiple owners, more easily very many of them than you could manage in a private sale. So why is the stock price not the actual value people see that slice of the company as providing them?