Subscription
With this model, you pay monthly/annually and receive free upgrades to the latest version as soon as it's released. It's a great option if you want to stay current with all the new features and improvements.
Lifetime License
This is a one-time payment that gives you permanent access to the software version you purchase. However, it doesn't include free upgrades to future versions. If a new version comes out, you'll need to purchase it separately to get those updates.