When configuring Motiva Message Testing AI, there's an option called Confidence Threshold. 

If the confidence of a particular variation reaches the confidence threshold, Motiva will automatically invest all future sends in that “winner” and stop sending other variations.

The default confidence threshold is our highest setting of 99%, but if you prefer, you can select a lower value, either 95% or 90%.

The higher the value, the more confident you can be that Motiva found the true "winner", but it will take longer to find.
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Also see Confidence.
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