A captain by any other name should manage just as well. That must be what South African cricket thought when the process to replace Graeme Smith as limited-overs leader began in August 2010.

Two and a half years on, they have been through four captains but have not found a long-term replacement. The search for someone who has security in team position, aptitude, and the willingness to do the job full time is still on, as concerns grow about AB de Villiers' suitability. It is something South Africa have to address seriously as they plan for three ICC events in three years.

Johan Botha was initially named Smith's successor and he was a good choice. Botha is a natural leader who is comfortable enough with himself to know when to delegate and when to take charge. His tactical acumen is solid and he thinks about the game in interesting ways.

But Botha was not kept in the frame for long. He was stripped of the role 11 months on, when South Africa's management structure changed. Following that, he was slowly shifted out of the team to its fringes. Eventually, sensing the end was near, he asked to be released from his national contract to take up a position at South Australia, where he would captain the state team in all formats. Botha last played for South Africa at the World Twenty20 last September and all indications from both him and the administrators are that he will not return to the fold.

When Botha was dislodged, a new think tank was put in place, with de Villiers and Hashim Amla as Smith's sidekicks. Although de Villiers had never captained a team before, at any level, his enthusiasm and team-man attitude made it seem he was perfect for the job. Amla was a less obvious choice, having always shied away from leadership, but he excitedly said he was ready for a different challenge and understood he would be de Villiers' understudy in limited-overs teams, even though he was not a regular in the T20 side at the time.

It has been 18 months since those decisions were made and questions are being asked about whether they were the correct ones. De Villiers appears increasingly uncomfortable with the role and Amla has shunned his part in it. Instead Faf du Plessis, who at the time of the appointments was only just starting to establish his place in the ODI side but has since become a regular across all three formats, has captained South Africa in a T20 series and will now take charge of the rest of the ODI series against New Zealand because of de Villiers' suspension.

A slow over rate cost de Villiers the chance to immerse himself in the intricacies of captaincy, as was the plan for this series. To that end, he gave up the wicketkeeping gloves so he could get a different perspective on the game.

It was this time last year, almost to the day, that de Villiers captained South Africa for the first time, against Sri Lanka in Paarl. South Africa won convincingly after scoring 301 and bowling Sri Lanka out for 43. De Villiers was hugely satisfied with the win but looked hassled. He confessed that because things had happened so fast, he wasn't able to have sufficient time with his bowlers to discuss field placements and strategies, and said he felt out of control as the match went on.

He has been in charge in nine more ODIs and eight T20s. Before this series, he said almost exactly the same thing he did after the crushing win over Sri Lanka. He still felt he needed to be closer to the bowlers so that he could communicate better with them and he said felt rushed on the field.

"Long before he was considered captaincy material, de Villiers made it clear he wanted to become the best batsman in the world and did not want to keep wicket. He has since, in the words of convenor of selectors Andrew Hudson "changed his mind" to the point where he was willing to sacrifice a year of his career to do the job"

That his concerns were almost identical to what they were a year ago could simply mean de Villiers needs more time to get to grips with captaincy. It could also point to his own uncertainty and indecisiveness, two traits that should appear only in very small quantities in a captain's kit but seem to feature more with de Villiers.

To illustrate that, consider that not only has he struggled to get to grips with leadership, he has also continually wavered about his role in the team. Long before he was considered captaincy material, de Villiers made it clear he wanted to become the best batsman in the world and did not want to keep wicket. He has since, in the words of convenor of selectors Andrew Hudson, "changed his mind" to the point where he was willing to sacrifice of "a year of my career" because of his bad back, to do the job.

When de Villiers was asked to take over as a limited-overs captain, it was put to him that the triple task of keeping, leading and batting would be too much. De Villiers did not agree with such suggestions. Neither did those who appointed him, specifically Gary Kirsten, although he has also changed his mind about that now and said he was "always concerned" the burden on de Villiers would be too great.

As a result, they have had to make a plan to rest de Villiers so he can continue keeping in Tests. He passed the gloves on in limited-overs, a dual solution that also allowed him to "focus on captaincy." It appeared a clever solution to all de Villiers' concerns but it did not ease the one about his ability, not willingness, to captain.

De Villiers continually claims to be unsure of the skills needed and the style of captaincy he should adopt. He has yet to find his way despite a reasonable amount of time in the job. He could have had even more time if he had gone to the unofficial T20 tri-series in Zimbabwe to June last year.

Instead it was Amla who took South Africa to that event, as a vice-captain rightly should. The same Amla who now wants the armband as far away from his shirt as the alcohol-manufacturer sponsor's logo.

Although Amla captained South Africa at Under-19 level and had a stint in charge of Dolphins, he has always been a reluctant leader. At Dolphins his period as captain coincided with a lack of personal runs, and that seems to have put him off captaining for good.

AB de Villiers and Tillakaratne Dilshan at the toss Getty Images

Still, Amla stood in for de Villiers once, in what was supposed to be de Villiers captaincy debut, against Australia in October 2011. De Villiers picked up an injury at the Champions League, so Amla led South Africa to a T20 series draw and ODI series loss. His own form suffered and he indicated it was not a job he would want again.

That view has not changed. When ESPNcricinfo spoke to a source close to the team minutes after news broke that de Villiers was ruled out of the remaining ODIs against New Zealand, they said it was unlikely Amla would take over. A CSA release later confirmed that Amla wanted to "concentrate on his batting" and that the selectors would grant him his wish.

Amla, like Jacques Kallis, obviously wants no part in captaincy. In being largely left alone to play his own game, Kallis has given South Africa more than any other cricketer. Amla may do the same. In which case he has to lose the vice-captain tag. He probably won't even notice its gone.

It should probably go the way of du Plessis, who has emerged as a candidate to take over the main job too. Du Plessis was a captain at school level and a former leader of South Africa's A side, and seems to enjoy the extra responsibility.

Promoting him, maybe even above de Villiers, should not be seen as an insult to de Villiers or Amla. It should rather be seen as responding to the changing times. When de Villiers was put in charge of the limited-overs teams he was not the Test wicketkeeper and his concerns about the captaincy had not been developed. Circumstances and experiences may require a shift in policy.

A decade of Smith meant that South African cricket had not had to debate about another leader for most of that time. Even when doubts about Smith started to emerge, it was always clear that he had the ability to lead and the presence that would prompt others to follow him. In two weeks' time, Smith will captain South Africa for the 100th occasion in a Test match. He is undisputedly the best captain this country has had, and if they want another like him, sensible decisions must be made to find one.