Reasons to buy in game list?

some time ago I decided to stop being so cheap and to not wait for offers and just buy the current Call of Duty and play it.

Now I see four CODs in the Blizzard launcher and would like to know more about them. Like… why should I care about them?

I own COD:MW and there is Warzone included and COOP missions and I can do mission alone in the coop’s private section, I am happy with my COD:MW.

Give us reasons to even LOOK at the other ones. Like… average player count, release date, difference to other CODs? Not sure.
I know that I liked the BlackOps CODs more than the other CODs, but I have no idea why. Different developer? What IS the difference?

Give us reasons to buy!