why don't they make it come back

They could have kept it going. They could have made it where they fallow him to Avalon and then bring him back to the time now. So that he can clean the land up again as he had done before. So far  one thing has come to pass an that is the Lady of the lake has come. Now we need Arther to take the throne. Then the sword to come forth. The round table is in the Abby on the wall. So that is there, Is there any one whom would love for the Merlin show to keep going. I would.