Check This on Day Two	Do Not Look at This
Are both variants receiving traffic?	Which variant is winning
Is the split roughly 50/50?	The conversion rates
Are metrics firing in both variants?	Statistical significance
Any spike in errors or complaints?	Whether you can stop early
Does variant B look right on mobile?	Anything that would tempt you to stop

A sensible practice: have someone who isn't the test owner do the day-two check, and report only on the left-hand column. It removes the temptation entirely rather than relying on your self-discipline at a moment when you're curious.

A/B Testing for Product Managers

Module 1Why Most A/B Tests Waste Three Weeks

Module 2Is This Even Worth Testing?

Module 3Writing a Hypothesis You Can Be Wrong About

Module 4Choosing the Metric

Module 5How Long It Needs to Run

Module 6Running It Without Ruining It

Module 7Reading the Result

Module 8Deciding and Shipping

Module 9The Six Ways Tests Lie

Module 10When A/B Testing Is the Wrong Tool

Module 11Final Project: Design, Run and Report One Real Test

Module 12Appendix: The Prompt Library

Module 13Glossary: Words Explained

What to Check on Day Two