AKA the Eureka Effect, Activation
In the context of digital adoption, the Aha Moment is the point that a user realizes the value of the product and knows exactly why they need it. In short, a user is looking for a solution, uses an app or product, and has a moment where they understand why this will prove very helpful.
Aha moments can be small or big, but to qualify, they should be a precise moment where the light goes on in a user's head. For example, if a user orders from a food delivery platform, the Aha moment can come when they've got a warm bag of food in their hand in a short span of time. It's at this moment they truly realize the platform's possibilities.
However, some companies use the Aha moment to measure when they know the customer will stick around. For example, Facebook's idea of the Aha moment is when someone adds seven friends within their first ten days. From here, they've found that the user understands the value of the platform.