diff --git a/smoke_test/generate_bin_test b/smoke_test/generate_bin_test
index 2883916cbf69bc9b817010248c31a8c7eeb2cffa..4d02d67425405a5c802615886a8d704658957898 100755
--- a/smoke_test/generate_bin_test
+++ b/smoke_test/generate_bin_test
@@ -1,4 +1,7 @@
 #!/bin/bash
+# NUM_MODULE does not necessarily corresponds to the output of `ls -l $TESTCASE_DIR | wc -l` because
+# 1. one folder is created for each software but NUM_MODULE pick combinations of from software/version 
+# 2. if a software does not modify PATH variable then there is no bintest generated for them, the number of those softwares are printed at the end
 NUM_MODULE=${1:-100}
 
 TESTCASE_DIR='./tests'