The name stands for "peer to peer". The platform here is not a seller but an intermediary: it brings the sides together and holds the cryptocurrency until payment is confirmed.
What you get
A rate closer to the market, because there is no service with its own spread standing between the sides.
What you take on
Time: the deal moves at the pace of a live person on the other end. Disputes: if payment is not confirmed, the platform handles the review, and that runs into hours or days. And source of funds: the transfer comes from a private individual rather than a company, which is harder to explain to your bank.
How this differs from an exchange service
An exchange service is a party to the deal, not an intermediary: it quotes the rate, answers for execution and settles itself. The price of that is the spread; what you get in return is predictability and a timeframe.
The main risk is not fraud but your bank
The platform protects the cryptocurrency with escrow, but it does not protect your card. If your counterparty settled with funds of questionable origin, the bank's questions will be addressed to you, because the money landed in your account.
Hence the rules experienced participants follow: do not accept payments from third parties, do not write "crypto", "USDT" or "exchange" in the payment reference, do not run dozens of small incoming payments in a row.
When P2P is worth it and when it is not
Worth it for small amounts and when you are willing to spend the time. Not worth it when the amount is large or the clock is against you: an exchange that waits on a live person's reply and may end in a dispute is a poor way to fit into an hour.
Read more: How to calculate the true rate of a P2P deal