In my experience, its a case by case bases, but in acqusitions, usually the main concern is employees. The executives are going to get paid out or ask to come aboard, and they want to make sure there employees and teammates are going to be fine after the acquisition. This could dictated whether the company is absorbed into the the acquiring company, like American Airlines and US Airways, or will operate as separate companies, like Zappos and Amazon , where they operate as 2 different companies but owned by one.
The second concern is most likely shareholder value. They want to make sure the they get top dollar for there company. In a lot cases executives are put in place by investors to make sure that very much happens. that includes making sure revenue is grown and costs are maintained so that when an offers made they could justify there value.