When you combine two companies, the focus should be on maintaining control of the current two businesses, control of the integration at large, maintaining customer satisfaction and securing the financial benefits. Synergy opportunities should be planned for in a timely fashion, but not at the expense of the customer. Once signatures are on the dotted line, CEOs must move quickly to implement the proper integration plan. Management teams lose sight of the customer. The customer is why we are all in business.
Mergers fall apart when the company focuses internally at the expense of the customer.
Everything should be set up to maintain the customer base, maintaining revenues, timely delivery of products or services. Managing the customer's expectations is critical. The ability to buy, take an order, ship an order bill an order and collect. All functional departments must be aligned in order to make this happen. It's all part of the organic process of a company seeking its focus.