Define success metrics for Marketplace serving consumers

Problem Statement Description

Product context: DoorDash is a local commerce and delivery platform; its products include restaurant delivery, DashPass, grocery and retail delivery, merchant tools, and dasher tools.

DoorDash operates a three-sided local commerce marketplace connecting consumers with merchants and Dashers across categories such as restaurants, grocery, convenience, and retail. In this interview, you are asked to define how DoorDash should measure the success of the Marketplace experience specifically from the consumer side.

Assume the consumer journey includes discovering available stores, evaluating price, fees, selection, delivery speed, placing an order, tracking fulfillment, receiving the order, and deciding whether to come back. Your metrics should help DoorDash understand whether consumers are finding value while also reflecting the realities of a marketplace where consumer demand affects merchant outcomes, Dasher supply, reliability, and unit economics.

This is a metrics design question, not a feature design question. The focus is on what should be measured, how those metrics should be defined, how they should be instrumented, and how they would guide product and business decisions for the consumer marketplace experience.

The experience should consider:

- A clear success metric hierarchy, including primary consumer success metrics, supporting funnel metrics, and marketplace health guardrails.

- Precise metric definitions, including numerator, denominator, time window, and whether the metric is user-based, order-based, session-based, or market-based.

- Key consumer cohorts such as new vs. returning users, DashPass vs. non-DashPass, high-frequency vs. low-frequency users, geography, category, and order occasion.

- Instrumentation needs across discovery, checkout, payment, fulfillment, delivery tracking, support, refunds, and reordering.

- Guardrails that prevent optimizing consumer growth at the expense of delivery reliability, merchant ROI, Dasher earnings, affordability, or contribution margin.

- How metrics should be interpreted across different local markets where supply density, merchant selection, delivery times, and competition may vary.

- Decision usefulness: how the metrics would help evaluate product changes, diagnose performance issues, prioritize investments, or compare marketplace health over time.

Your goal is to propose a practical measurement framework that DoorDash leadership and product teams could use to judge whether the consumer marketplace is succeeding, identify where the consumer journey is breaking down, and make trade-offs that preserve long-term marketplace health.