If the redo log file is mirrored, and before OS completes writing the mirrored file, the archive process tries to start copying, but it fails. Later it completes.
This type of "Wait and Complete" can be seen very often, when both hardware level mirroring(RAID 1) as well as manual duplexing the redo log files in the mirrored disk are configured. If RAID 1 is configured, then do not duplex the redo log. If you still want, then do it non-mirrored disk.