"I made a big mistake, which was to start off by winning four titles," Benitez, who took over at Anfield in the summer of 2004, told a forum in his native Madrid on Wednesday.
"Then people ask more of you, when in reality in the Premier League it's taken for granted that a manager needs time at the start to adapt."
"My future is Liverpool and I have had no offers (from other clubs)," he said.
But American owners Tom Hicks and George Gillett put the club up for sale last month and British media have reported the club's debts are more than 350 million pounds ($499 million).
"I have had a couple of meetings with the new (chairman Martin Broughton) to clarify the situation," Benitez said.
"We need to know how much money we have, and that also depends on (player) sales."
