"when storage is bought, it will last forever" how exactly will this work?!

In the FAQ (https://safenetwork.wiki/en/FAQ) there is this paragraph:

it is anticipated that storage will be significantly cheaper than using any current solutions. It is important to note that when storage is bought, it will last forever and is not just provided on an annual basis.

As I understand this statement it means: “Pay just once for the storage and can use it forever without any other payments”
How is this supposed to work when the farmers expect to be payed regularly for providing storage?