Paraphrase the following: only armchair politicians are immune from committing mistakes, errors are inherent in political struggle, who have to deal with practical and pressing problems, are afforded little time for reflection and no precedents to guide them and are bound to slip up many times.

APA:

According to Mandela (2010), in politics many of the individuals who work in these offices or fields experience insistent and pragmatic obstacles, and because of this, many are sleep deprived and are impeded with self-guiding introspection. Thus, the outcomes involving such behaviors only contribute to many of these politicians', bound to exhibit such errors, these errors then are inevitable for most of these individuals. Although, some sectors like the armchair politicians are the only ones protected if errors are done. But other politicians are bound to answer cases. 

Reference: Conversation with myself by Nelson Mandela. p. 35. London: Macmillan, 2010