1. Look for common threads.
Ask yourself: will the direction my company is taking address my customers’ needs in the long run?
If you have done your homework as a product manager you should know what your customers expect from you. Look for a common thread between the customers' needs and the shareholders' interests. Sometimes they are in fact very similar.
2. What if there is no common thread?
Make sure your product offers something that satisfies your customers in addition to what was promised to your shareholders. There is always room for more customer features. It may be a hard sell to upper management, however it must be noted that the the consumers pay the bills. If you lose your customers' business, it will be detrimental to your shareholders. Have data to support this point; executives will agree with your reasoning if you have the numbers to support it.
3. You are overruled by the executives.
In the case that your customers' requests go unanswered, be prepared to discuss this with the customers. Being frank and honest goes a long way. If executive management is unresponsive, you may want to schedule a meeting between the customer and management so each party can voice its concerns. This step is especially important if it is a major customer who will be affected.
If after taking these measures management has not satisfied the consumer, be ready to concede defeat. Perhaps it is time to find a company that is more attuned to the consumers' needs.