I have been using StackOverflow for a while and recently became familiar with how the site works. I have a fundamental question on how the answers are displayed on the site. I already tried searching for the topic but I could not find an answer. Also, I am quite sure that I am missing something here as people have been using these sites for a while and nothing beats experience. So please take the following as an attempt to learn the model better than anything else.
Currently most of the content on the site is in the form of a single question with multiple answers. Among these multiple answers one of the anwers maybe the best choice. In some cases, there maybe more than one best answers each providing a different acceptable solution. Along with this relevant information, there is lot of not so useful information. In the ideal case, the reader would like to see only the most relevant and best information. The current format has following issues:
The current format uses the chosen answer (which the person asking the original question does) or the number of votes as an indicator to bubble up the most useful information. Both of these indicators are influenced a great deal by when the answer was given. The person asking the question may accept the first suitable answer and move on. The quickest set of answers may receive more votes. So later on if someone comes up with a better answer, it may not even be read by subsequent visitors to the site as it starts with a vote count of 0.
Provided the best answer has been identified, what is the benefit of having any content other than the best answer displayed at all?
On the other hand, community wiki only model where the quality of a single piece of information is improved over time, does not suffer from either (1) or (2) above. One example is Wikipedia. On Wikipedia, there is just one piece of information related to any topic the quality of which improves over time. In fact, even on stackoverflow, the community wiki pages seem to have the most accurate and well formed information with a quality better than regular answers.
I understand that the site allows editing of answers but but than why allow each person to have their own answer rather than trying to improve a single wiki (shared content).
If community wiki is the only option then the contributors will have no choice but to improve a single piece of information. In fact, community wiki can even have alternative answers to the same question.
So my question is: what is the advantage of having multiple answers over having only community wiki? What is the thing that community wiki can not achieve? I already listed the advantages of community wiki over multiple answers approach.
Of course the reputation system has to be devised/ modified for the community wiki model. What am I missing here?