Introducing Statistics: Worry About Error Practice Test

A retail company A/B tests a new checkout design on a sample of website visitors and finds evidence of a higher purchase rate. The company considers rolling it out to all users immediately. Why is it important to consider potential error in this inference, given that a rollout could either increase revenue or unintentionally reduce sales for many customers?

A pharmaceutical company runs a clinical trial on a sample of patients and finds that a new drug appears to reduce symptoms more than a placebo. Regulators must decide whether to approve the drug for widespread use. Why is it important to consider potential error in the statistical inference from the trial when making this approval decision?