Starbucks expects its baristas to complete a drive through order in no more than $50$ seconds $($Heather Haddon, "Starbucks Is Rethinking Almost Everything, Including How to Make Frappuccinos," The Wall Street Journal, August $31,2022).$ Suppose that the management intends to redesign and retrain at any store whose average is not $50$ seconds.

Starbucks Embraces the Drive$-$Thru $-$ Bloomberg

A management team observes a sample of $100$ customer orders at a particular store. The average order is completed in $58$ seconds, and the sample standard deviation is $3.$

Even though the average time is over $50$ seconds, why should the team do a hypothesis test before proceeding?

The average time is from a sample. A hypothesis test can help the team know whether the average of all orders is greater than $50$ seconds.

A hypothesis test can help the management team prioritize which stores are most in need of redesigning and retraining.

A hypothesis test can help the management team know why the average is higher at this store.

A hypothesis test can help the management team decide whether it's worth the cost to redesign and retrain.

A hypothesis test can help the management team know whether the times were affected by the barristas knowing that they were being observed.