Ferrari have been unable to match the performance of Red Bull because some developments introduced during the season had a negative effect, according to team boss Stefano Domenicali.
Lead driver Fernando Alonso is trailing Sebastian Vettel in the drivers' standings with the German close to securing the title, and Domenicali believes that the Marinello outfit were unable to maintain a competitive package throughout the season.
He told AS: "The problem is that we could not improve the car steadily, because unfortunately in some cases we brought developments that, instead of improving, actually worsened the car."
Vettel can seal his fourth consecutive world title at the Indian Grand Prix on October 27.