Email marketing automation (early 2000s)
Email marketing moved from manual blasts to automated, behavior-triggered campaigns as platforms like Mailchimp and later Klaviyo built tools that sent the right message based on what customers actually did. Revenue became attributable per subscriber and per flow.
Email became the highest-ROI channel in ecommerce, with automated flows recovering abandoned carts and driving repeat purchases.
Automation turned email from a manual chore into a programmatic channel every brand could afford, setting the template for SMS and now phone.
Outbound phone sits at the same inflection point: human-dialed calls are becoming programmable campaigns with per-call revenue attribution.
