What are the different statuses?

There are 5 different status possibilities:

Messaged means your shopper was messaged by the app after they commented and were asked about the variant option. But they did not click on the variant option in Messenger (and thus did not get properly invoiced)

Invoiced means your shopper successfully got a checkout link to purchase. 

Bought obviously means you made a sale!

Waitlisted means they were waitlisted after they commented. This article explains how waitlists work

Removed is the status when the shopper clicks the "Remove from Cart" button

There is another possible status called "Error" which happens when the shopper's privacy settings prevent your page from contacting them in Messenger or when your page tries to message itself

This article explains the different reasons why an error might happen.