Why Mergers and Acquisition Happen

I often see companies merge both private and public, and have to scratch my head and say what was the reason behind that merger? There are many reasons for Mergers and acquisitions to happen, some good and some bad. Good reasons are for operational synergy for financial synergy. Mergers made because they bring economy of scale or lower the cost of capital can be good. There are many bad reasons like managerial pride. This is one of the main reasons that many mergers fail. When management feels they need to acquire a company to make themselves look busy, many times they over pay and the long-term results of this are disastrous.