"People need to understand that to win trophies is really difficult. More and more teams are spending more and more money," said Benitez.
"We will try to be closer and have a lot of confidence because the squad is better, but you can't guarantee anything. We must make sure we do our best ever time.
"I'm surprised when some of the experts criticise us. They don't analyse the situation, the bigger picture of the Premier League and the levels of the other teams.
"As a manager, you have to analyse things properly, because you aren't a fan. You have a responsibility. You can't just say what people want to hear.
"The Premier League is becoming more and more difficult because so many people are spending money. La Liga is fantastic, but now the Premier League is better and more difficult.
"For us to qualify for the Champions League for five years in a row is important for a club of our stature. We want to win trophies, and to win the Premier League would be amazing. But it's not easy."
