clarification of 10 GB available space and unlimited total submission storage

I would like to know what your mean by 10 GB available space and unlimited total submission storage in the Bronze Plan

Submission storage is the total number of submissions that stored in your account across all the forms. For free accounts, the submission storage is limited to only 500 submissions. However, paid users don't have any limitations for submission storage.   

10 GB available space means 10 GB upload storage space. To clarify, your form users will be able to upload files to your forms up to 10 GB. The uploads will be stored on our servers. Please note that your upload storage space does not reset to zero every month, unlike monthly submission counts. If you exceed your upload storage space than you will need to delete submissions in order to open available space for file submissions.