The options are priced by markets with liquidity in them. If markets became illiquid from many withdrawals, it may become more costly to exit an option position.
However, keep in mind that because each option is collateralized 100%, the options can always be exercised for the assets. This is a guarantee of zero credit default risk.
Using the protocol does not come risk-free. A material loss of user funds can occur if a Primitive smart contract is exploited and drained of funds. In that scenario, the options would instantly become worthless since they would have no claim on any tokens (there would be no collateral in the contracts to redeem the options for).
Please visit the risks page on the interface to learn more: Risks Page.
The core option contracts were audited by Open Zeppelin.