A sync project, which synchronizes in the direction of the target system, writes the error messages in the log during sync and then continues (Exceptions handling: Continue on error).
In the case of bulk processing, this means that every entry for an object in the log always contains all messages from the previous objects in the sync. The LOG buffer is not emptied during bulk processing. This happens both with write access (OnCommit ()) and with read access (OnReload ()).