diff --git a/src/support/os.cpp b/src/support/os.cpp
index 9a901cfd02..d34adee420 100644
--- a/src/support/os.cpp
+++ b/src/support/os.cpp
@@ -129,6 +129,7 @@ static string const find_python_binary()
 	}
 
 	// last chance: try the unversioned name
+	// This case is very common on Windows.
 	if (command.empty())
 	  command = python_call("python");