https://datatracker.ietf.org/doc/html/rfc6762#section-14

To protect the network against excessive packet flooding due to
software bugs or malicious attack, a Multicast DNS responder MUST NOT
(except in the one special case of answering probe queries) multicast
a record on a given interface until at least one second has elapsed
since the last time that record was multicast on that particular
interface. A legitimate querier on the network should have seen the
previous transmission and cached it. A querier that did not receive
and cache the previous transmission will retry its request and
receive a subsequent response. In the special case of answering
probe queries, because of the limited time before the probing host
will make its decision about whether or not to use the name, a
Multicast DNS responder MUST respond quickly. In this special case
only, when responding via multicast to a probe, a Multicast DNS
responder is only required to delay its transmission as necessary to
ensure an interval of at least 250 ms since the last time the record
was multicast on that interface.