The Reds were untroubled as they cruised to victory with goals from Martin Skrtel, Steven Gerrard, Stewart Downing and Luis Suarez.
Jol conceded Fulham had let themselves down.
"We conceded cheap goals and then we played against ourselves because there were too many disappointments," said the Dutchman.
"Overall it wasn't good enough."
Fulham have now won just once in their last 10 matches and this was their second successive defeat.
Jol could be forgiven for looking anxiously over his shoulder, with just five points separating the Cottagers from the drop zone, but the Dutchman is confident his side will steer clear of trouble.
"We're on 20 points and we have a bit of a cushion," he said.
"We've had a lot of injury problems, but once those players are back we will be fine. We played some very good football before and I'm confident we will do that again.
"But there's no doubt that we have to pick up the points and do better than we did today.
"The next two games are very important. We've got Southampton and then Swansea City; both at home, but we need to show more conviction."