Stakeholders are any people who stand to be harmed in some way if a business is run badly. Such people also tend to benefit if the business in run well. Stakeholders, then, can either benefit or lose if a business decides to offer a particular product or service.
Take the new Amazon Kindle Fire, for example. Amazon has put a great deal of resources into creating and marketing this product. If it does not sell, Amazon stock prices and dividends will likely go down, hurting some stakeholders. If, on the other hand, it becomes a huge hit, Amazon may need to expand, thus benefitting those stakeholders who own its shares and those who work at Amazon, among others.
Thus, each new offering is a risk-reward proposition. Stakeholders can gain if it goes well or be harmed if it does not.