To improve both performance and delivery, add additional supply so your high-performing line items reach a wider audience in Amazon Ads campaigns.

• Supply setting will have no effect on this
• Reduce supply
• Add additional supply

The correct answer is: Add additional supply

Explanation: When a line item in your campaign has high performance but is experiencing low delivery, it means that the ad is engaging well with its current audience but is not reaching enough people. In such situations, optimizing delivery is crucial to maximize the impact of your high-performing ads. The best approach is to add additional supply—such as expanding inventory sources, increasing targeting options, or including more placements—to broaden the reach of the campaign. This way, more users are exposed to your high-performing ad, allowing for greater impressions and potentially better results, while maintaining effectiveness.

Reference: https://advertising.amazon.com/help/GJHF6GB7WZUMPYJ6