The Faenza based team slipped to ninth in the championship with just 26 points, which included a run of nine races without a top ten finish.
"Toro Rosso is still our rookie team and its goals differ from those of Red Bull Racing," Mateschitz told AUTO, the FIA's new magazine.
"But that’s not to say we’re happy with the development of the car. Significant improvements need to be found and are being called for", he added.
Toro Rosso dispensed with Giorgio Ascanelli after the British Grand Prix and hired former Sauber technical director James Key.
On the driver front, the team retains Daniel Ricciardo and Jean Eric Vergne into 2013.