You can only download a certain amount of files per week and month. With this limitation we want to encourage a reasonable use of our platform. Members should download the files they need, not as many files as possible.
The Letter Library does not only pay for file storage, but also for file delivery (“egress charges”). If every supporting member would download the entire file archive, the hosting costs would be much higher and therefore the membership costs would have to be much higher too. By enforcing download limits, we can keep the prices reasonable.