This free-text field supplements the numeric transfer-status code with a human-readable explanation of exactly what happened during the file transfer, or confirms successful completion with additional detail. An admin troubleshooting a failed firmware push would read this text first, since it often names the specific cause, such as permission denied or disk full, that the enumerated status code alone can't convey. A typical value might be 'Transfer completed successfully, 42 MB in 18 seconds' or 'Connection timed out after 3 retries'.