Few other considerations on this topic as as follows:
1. Acquirer materially overestimates the synergies a merger will yield. These synergies can come from economies of scale and scope, best practice, the sharing of capabilities and opportunities. It takes only a very small degree of error in estimating these values to cause an acquisition effort to stumble
2. In the absence of a common vision and a clear statement of what the merged company will stand for, how the organisation will operate, what it will feel like, and what will be different compared to how things are today, there is no point of the convergence on the horizon and the organisations will never blend.
3. There is not much importance given to cultural assessment and integration due to which the acquired company does not fit into the target eco-system and retention becomes a key issue.