"The default setting for the membership plugin is to disable user accounts that do not complete

Hi-
Clarification on what this field means in Membership>Edit Options>User Registration
"The default setting for the membership plugin is to disable user accounts that do not complete their subscription signup.
If you want to change this, then use the option below.
Enable incomplete signup accounts"

Enable incomplete sign ups means that they can start posting content/ using the membership services even though they didn't pay? Or am i reading this the wrong way?

Thx