Maybe Cthulu put it off to long.   
  
If he just pops up out of the abyss, we will put an armor piercing round between his eyes and be home in time for dinner.   
  
Maybe we would catch him in a carbon fiber net and put him in a giant fish tank to amuse our children.  Maybe we will slice him up into 20,000 tons of calamari and throw a big party.
  
He still wants to come back and return our puny world to the old ways, but now he needs to make the world ready to accept him.  
  
Instead of simply crashing through our cities and sacred places, devouring our souls, he has to offer something for them. Perhaps he sells knowledge of the future and buys people's souls.

His long term plan is to create medicines for treating mental illness. After his company has cured Parkinsons, schizophrenia and alzheimers, he will reveal himself as the dark master behind the corporation and ask to peacefully co-exist. For now...