Is a loan marketplace really peer-to-peer lending? What do investors actually buy?

In traditional peer-to-peer lending, the platform only matches investors with borrowers, and investors have a direct claim against the borrower.
On loan marketplaces, the structure is usually different. A lending company (the loan originator) makes and services the loans, sells the receivables to a separate company (often a special purpose vehicle), and that company issues notes that investors buy. Your claim is then against that company, not against the borrowers, and repayments flow from the originator through it to note holders.
This means your return depends on the originator's financial health as much as on the borrowers: if the originator gets into trouble, payments to investors can be affected. Notes can also be harder to sell than the loans themselves, so you may be locked in until the loans are repaid. Capital is at risk: crowdfunding investments are not covered by deposit guarantee schemes, can lose part or all of their value, and may be hard to sell before the end of their term.