What is the main goal of e-commerce marketing? Profit and growth demonstrated over time. The performance measure used to understand and analyze profit over time is called Return on Investment, or ROI. In e-commerce marketing, ROI analysis is usually alongside or preceded by Return on Advertising Spend (ROAS). The key to increasing ROI/ROAS, and consequently profit performance, is attribution. Attribution calculates the return on investment for advertising media channels, which have developed user traffic in e-commerce.