Domain events are past tense, always

An event names something that has already happened and cannot be refused, which is the property that separates it from a command.

// events — past tense, immutable, may have many listeners
final class OrderPlaced {}
final class PaymentCaptured {}
final class StockReserved {}

// commands — imperative, one handler, may be rejected
final class PlaceOrder {}
final class CapturePayment {}

// the smell: an "event" a listener can veto.
// that is a command wearing the wrong name.

The naming convention is not cosmetic — it decides who is allowed to fail. A handler for OrderPlaced that throws does not un-place the order, so it must either retry or record its failure somewhere; a handler for PlaceOrder that throws means the order was not placed. Conflating the two produces a system where an email failure rolls back a sale, which is how these mistakes are usually discovered.