Click models only see clicks. If someone watches your Instagram ad, doesn't tap it, and later searches your brand on Google, the click credits Google. That is why many teams add a "How did you hear about us?" question. The hard part is collecting the answers consistently and making them comparable.
BrainyMetrics picks the answer up automatically from your forms (a text field, dropdown or radio group whose label looks like the question), from tracko('identify'), from the API, and from Shopify order note attributes written by post-purchase survey apps. Each answer is kept as typed and mapped to a bucket such as Facebook, Instagram, YouTube, TikTok, Google, podcast, influencer, word of mouth or AI assistant.