The Reds were beaten 3-0 by Watford on Sunday afternoon.
The German was brought in to replace Brendan Rodgers at Anfield back in October following a disappointing start to the campaign.
After a bright start, they have slumped in recent weeks, with them now without a win in four games following the 3-0 loss to Watford on Sunday afternoon.
That game highlighted several issues with Liverpool at present and Souness says there is no quick fix for the former Borussia Dortmund manager.
"I don't think the players are good enough and there's a lot of work ahead for them," he told Sky Sports.
"They got off to a terrible start but you are looking for a reaction at that time and for the players to be angry and not to feel sorry for themselves.
"The bottom line, when you cut away all the excuses, [is] are they good enough? It's not a quick fix. They've got some decent players and some that might get better but it's going to be a long road for them."
If there is one area Klopp is surely keen to improve moving forward, it is the options he has up front.
His side have only managed 20 goals in the Premier League so far, an average of 1.1 per game, the same as relegation threatened Newcastle United and Norwich City.
Their top goal scorers are currently Christian Benteke and Philippe Coutinho with five a piece in all competitions; a poor tally for a side with Champions League aspirations.