Mohammad Razmjoo

I thought always we must do jumper wiring for one side of our output relays?!! Is that false??

No, you're right.

The connection terminals for the outputs are potential-free make contacts of the output relays. 

Must you ask person who has made example ... 

I don't no why ....

From the same web site:

What you show is a mistake that can happen. The author of this article was just not paying attention.