There are several reasons why you would want to merge visitor profiles that have been determined to belong to the same visitor. By gathering together all the profile properties and their values in one profile, you create a richer visitor profile that contains the most complete information about the visitor's behavior across multiple channels. This makes it possible to target more meaningful dialogues at the visitor. Profile merging also reduces the total number of visitor profiles in the BlueConic database, which can improve BlueConic's performance. By streamlining visitor profiles using profile merging, you also guarantee that segment values are as realistic as possible.
Only merge profiles when you are certain they belong to the same visitor. If you are not sure two profiles are the same visitor, merging them will actually result in a less meaningful merged profile. It is better to not merge two profiles than to merge on a gamble!