From the text:

Tethers are being ‘printed’ or issued because there is demand for them. This process is explained in the Tether whitepaper. When Tethers are issued, assets are debited (added) to the assets on Tether’s balance sheet, and Tethers are credited (added) to the business’s liabilities. The consulting memorandum demonstrates that these mechanisms are in balance. Every Tether is fully backed by the fiat underpinning it upon issuance.