@miojamo - what @laurentiu and @Dev1@OptiBiz1 said are both valid points.
If you run the command correctly you should see something back, anything. If you don't, then maybe you are running the command as a user and the files are owned by another user and somehow you don't have permissions to run them.
I do launch them as root. I think there is nothing in the queue therefore there is no output. The problem is with the email about error sent about 100 times per day I had to disable the cron jobs.
One more thing sending mails work it only the error: /bin/sh: 0: Illegal option -