Explain and test completion-rate gaps

In a food delivery marketplace, orders containing alcohol complete at a lower rate than orders without alcohol.

Respond to the following:

1. Give several plausible business or operational explanations for why alcohol orders might complete less often.
2. Describe what further data you would examine to check those explanations.
3. Assume the company runs a simple randomized intervention intended to raise completion. Explain how you would assess the effect with a two-sample t-test. Cover the null hypothesis, alternative hypothesis, assumptions, the test statistic at a high level, and how you would interpret the outcome.

You do not need to use a time-area switchback design for this question.

Overview: This question tests understanding of causal inference, product-metrics analysis, experimental design, and statistical hypothesis testing (including two-sample t-tests) in the context of operational problems in a marketplace.