City failed to defend their crown as champions of England, but Argentine full-back Zabaleta feels it is easy to pinpoint where they went wrong.
City have lost just one more game than United, but they have drawn eight - five more than their arch-rivals.
Now Zabaleta and City are focused on winning the FA Cup next month, before regrouping and making another attempt for the summit of English football.
"For Manchester City it is important to keep winning trophies every year," he told Sky Sports.
"We know how difficult it is in the Premier League and also Europe you play against big teams and this season we have been inconsistent and that cost us the title.
"United have been more consistent. They have been better and kept winning and they deserved the title.
"We just need to keep working and be positive because if you look at the team we have fantastic players and want to bring more success."