Google uses machine-learning technology to analyze your existing campaigns and automatically creates custom intent audience suggestions. These audiences are based on the most common keywords and URLs found in content that people browse while researching a given product or service.
For example, insights from existing campaigns may show that people who’ve visited a sporting goods website have also actively researched rainy day workout shoes. Google Ads may then auto-create a new “waterproof trail running shoes” custom intent audience that can simplify the process of reaching this niche segment of customers. These audiences are constantly refreshed, which may lead to improved performance over time.