If God knows everything then how come it has taken him so long to end the tyranny of Satan?

I mean wouldn't he destroy all of Satan's defenses and bring Satan upon the brink of destruction within a couple of seconds seeing as though he knows everything about Satan's battle plans and such. So the thing is why has it taken so long for God to carry out the final battle? Why has it taken at least 10,000 years for God to carry out the Battle for Armageddon?