A question about connectionTimeout and connection

Hello, I Use curator as follow:
CuratorFrameworkFactory.Builder builder = CuratorFrameworkFactory.builder()
.connectString("xxx") //this xxx includes 5 invalid IP address.
.sessionTimeoutMs(10_000)
.connectionTimeoutMs(10_000)
retryPolicy(retryNtimes(3,5000));
client.start();
I try to test curator's timeout action when curator first attempt to connect zk server. I think curator(actually internal zookeeper client) will not try to connect server after it retry 3 times and connectionTimeout，but actually I see the log file，zk client seems not controlled by curator? the zk client always throw some exception, such as connectionLossException... never stop until I stop my program.
I use curator not long ago, and try to read curator code. But I still can't understand why curator behavior as described above.
Hope to receive your reply soon.
Thank you.