Monday's 11-run defeat by Pakistan in St Lucia, following their loss to England [ Images ] on Saturday, was in marked contrast to South Africa's unbeaten run to the last four in the same competition in 2009.
"Going into that tournament last year we had played a lot together as a team, we were coming off one of our most successful seasons and the confidence in the group was good, players were playing well, everyone knew their role," Smith told reporters.
"Here we have come out of eight weeks of not being together and haven't really gelled in terms of performing our roles and the confidence doesn't seem to be there.
"We seem to string one discipline together every game, not all three. Maybe it needs to be looked at in terms of the player group and maybe (we need) some fresh faces, some new energy -- that's something the selectors need to decide," added Smith.
"The team is more important than any individual really and it is about getting the right players involved to be successful," he added.
A team with bags of talent, including Jacques Kallis [ Images ] and Herschelle Gibbs [ Images ], failed in both defeats to keep up the tempo in a run chase and Monday's batting display was particularly lacking in rhythm.
"I don't think it was tactical, it was just guys out in the middle making decisions," said Smith.
"Ultimately we kept losing wickets throughout and never found any flow or momentum to our innings, we never really changed the momentum at any stage.
"I think it's a bit of a confidence game, if you can get a good score under your belt early on and get that confidence it allows you to play with some freedom.
"It is the same with other teams, one day the top order comes off and then the other game the middle order posts the total.
"It's about having a group of players with confidence that really believe and know the game very well and know their strengths, those teams that have been successful are doing that," added the skipper.
Smith said Australia were the favourites for the title and England were their main threat.
"I think Australia are playing the most dominant cricket, they have beaten teams comprehensively throughout this tournament," said South Africa's opening batsman.
"England played positive cricket against us, if they can maintain that level of play I think they are probably the one team left that can challenge Australia's pace attack," he added.