Listing plans clarification

I seem to misunderstand how the listing plans work. What I want to have is a an option for certain user accounts to be able to post one featured listing and unlimited standard listings. I thought that I should create the plan and set the featured listings to 1 and standard to 0, however the user can select this plan repeatedly and post multiple featured listings. The plan is set never to expire.
Looks like I have to create two separate single listing plans, one for the featured listing with Limit use of plan set to 1 and another for the standard listings and set Limit use of plan to 0, and finally set them to be visible to this account type only.

What I don't get is how is "listing plan" used. Can someone clarify? Thanks!

Anyone? :( The logic behind the listing plan completely eludes me. :)