diff --git a/cmd/mxl-pattern/main.go b/cmd/mxl-pattern/main.go
index 213e980..58691d9 100644
--- a/cmd/mxl-pattern/main.go
+++ b/cmd/mxl-pattern/main.go
@@ -92,6 +92,7 @@ func checkArgs(args appArgs) {
 	fi, err := os.Stat(args.domain)
 	if err != nil || !fi.IsDir() {
 		fmt.Fprintf(os.Stderr, "Invalid MXL domain: %s\n", args.domain)
+		fmt.Fprintf(os.Stderr, "Reason: %v\n", err)
 		printUsageAndExit()
 	}
 	if ok, err := mxl.IsTmpFs(args.domain); err != nil || !ok {