I always rated COD 1 as my least liked in the series because the campaign is too short and very dated graphics, but still cod 1 is my most played COD i keep replaying cod 1 over and over again,if COD 1 is my least favourite cod game why i keep replaying it ? after i finished COD WOW i finally realesed why,simply, the later COD's(Cod 4 MW,Cod MW 2,Cod WOW and to some extent Cod 2) are not enjoyable to play in single player.COD 1 gameplay is very straight foward you kill enemies you advance to objective,gunplay is very good you know when you hit your enemies and the visual clarity is clean,COD 2 introduced the shit "enemies keep respawning until you move to a certain point" cod 4 made it worse by adding infinite enemies respawn,gunplay in cod 2 and specially in later cod's got worse and worse you barely know if you hit someone in SP and weapons became worse to aim too,visual clarity got worse too ! (too much smoke and bullet effects too much enemies respawning in every corner too),COD MW 2 has a shitty blood visual effect that cover all over you screen when you in low health which makes impossible to see anything and if you are playing on veteran 30% of the time you ain't going too see nothing ! COD WOW and COD 2 are too repetitive ! is just same shit (you allies and enemies keep respawing until you move to trigger point).COD 4 also enemies keep respawing and visual clarity is awful but atleast the game have a good narrative and pacing to compesate.
So overall i think COD 2 added a huge decline to the gameplay and its only got worse and worse.I still like all COD's but the only one i bother to replay is COD 1,do you guys feel the same about the COD series ?