The Croatia international has stressed that a team of Los Blancos' stature should do better, but he has nothing but praise for former manager Jose Mourinho.
The Santiago Bernabeu side was beaten by Atletico Madrid in the Copa del Rey final after Borussia Dortmund ended its Champions League dreams, while Barcelona proved to be too strong in La Liga.
"We cannot be pleased with how this season went in general," Modric told Marca. "A club like Real Madrid cannot afford to go trophy-less."
The 27-year-old midfielder then had his say on Jose Mourinho, who left Madrid for Chelsea this summer after three years at the Bernabeu.
"I can only speak well of Mourinho. He's a fantastic coach. It was a pleasure to work with him. He taught me how to play more aggressively," Modric said. "He always tries to get more than the best out of every player. If you give 100 percent, he asks for 110. If you don't play to the best of your ability, someone will come and take your place."
Real Madrid has yet to hire Mourinho's successor, although PSG manager Carlo Ancelotti is widely thought to be a leading candidate for the role.