Think of it much like Microsoft Office 365, but with for creative minds. By installing the suite today and continuing the monthly (or annual) payments, you'll receive all future updates and major releases. The beauty of Adobe's Creative Cloud platform ensures you're always rocking the latest release of its software packages, and Premiere Pro is one of them. If you happen to be developing a YouTube channel or wish to take the plunge and become the next big name in the video editing biz, Premiere Pro will be your best friend for life.
You need to make sure the cost is outweighed by the functionality you'd be able to use regularly. It's pricey, coming in at $21/month for the Creative Cloud subscription (and that's just for one app if you subscribe for 12 months!). Pretty much everyone knows about Adobe Premiere Pro, but not everyone needs Adobe Premiere Pro.