why? populars games that worked trhought the years are all based on a ranked sistem that keeps the player playing the game , this is the basic for a game like apb, try to remove ranked sistem from overwatch or league legends and u will see how fast he dies.
This game dyed cuz it hasnt any ranked sistem if it had one , maybe was popular
P.s. I'll make u an example , i played league of legends for 6 years , the last 2\3 years i rly hated the game , but kept tryharding on it until i got the master rank , then finaly quit.
If there wasnt a ranked sistem u can be sure i quitted the game years before , and maybe didnt even play it for more then 2 mounths , and like me thousand of players.
Ranking sistem gives addiction , forcing u to play and improve , thats a fact.