Contact Queue not routed to an agent

I found something new in CRS CSQ configuration, something interesting a unknown for me.

The problem was regarding 2 CSQs – one was with criteria Most Skilled and second with Most Skilled by Weight. Additionally agent had another queues configured and those had been receiving calls with no problem. Those was no routed. Long long discoveries showed that if there are CSQs with more than one skills and those skills are assigned to others CSQs, an agent will not recieve a call until all that queues will be assigned with minimum competence to agent.

So if there is a CSQ with skills a,b,c,d from queues A,B,C,D and agent has got assigned skills a,b,e,f then an agent will not receive any call from CSQs A,B until it will be assigned with CSQs A,B,C,D. In that case if faced such issue then add agent to proper CSQ or reconfigure CSQ by removing skills c,d. Of course assure, it will not touch call routing for others agents.