Our batting and fielding needs improvement - Alastair Cook
Needing 382 runs for a victory in the final innings, England collapsed like a pack of cards getting dismissed for 101 with James Taylor's 24 being the highest score.
The England batsmen had no answer to Kagiso Rabada's pace as the 20-year-old picked 13 wickets in the game to register his career best figure of 144 for 13.
Needing 330 runs for victory on the final day, Cook revealed that the initial plan was not to aim for the target considering the uneven bounce on the pitch.
"Trevor [Bayliss] described it as limp batting.
"I don’t have a perfect way to describe it.
"We spoke this morning about 330 is a long way away in this wicket but for us to get into the game we needed a good start, build a partnership and get these guys into their second and third spells."
England's newly adopted aggressive approach has reaped them huge benefits recently but Cook believes they need to strike a balance.
"Sometimes whatever you say means nothing, it is about what you going to do.
"Today we didn’t do it.
"We need to get the balance right between attacking nature which we want to play in but sometimes you can’t play that way."
Apart from regular batting collapses another factor which hurt England the most, especially in the longer format is dropping regulation catches.
In the first innings of the Centurion Test, England dropped Hashim Amla and Stephen Cook early while also handing a couple of reprieves to Quinton de Kock.
All the three batsmen went on to notch centuries as South Africa went on to score 475.
Admitting England are nowhere close to a "finished article", Cook urged on the need to improve their batting and fielding in order to be consistent.
"We're nowhere near the finished article and there are huge amount of work to be do especially in our batting and fielding and that’s exciting especially on the back of a 2-1 win."
Eoin Morgan will now lead England in their limited overs leg of the tournament which consists of five One-Day Internationals and two Twenty20 Internationals.
© Cricket World 2016