Update insert-functions.md

Author: spencerattick

src/connections/functions/insert-functions.md

@@ -199,6 +199,9 @@ You can manually test your code from the functions editor:
 - Error messages display errors surfaced from your function.
 - Logs display any messages to console.log() from the function.
 
+- > info ""
+> Please note that the Event Tester will not make use of an Insert Function. It will not show how your data is impacted by an Insert Function and it will not allow data to be sent downstream through the Insert Function pipeline.
+
 ## Save and deploy the destination insert function
 
 Once you finish building your insert function, click **Next: Configure & Create** to name it, then click **Create Function** to save it.