(1) Lack of Personal Security.
https://en.wikipedia.org/wiki/Private_security_industry_in_S...
The private security industry in South Africa is the largest in the world,[2] with nearly 9,000 registered companies and 400,000 registered active private security guards, more than the South African police and army combined
(2) White flight, wealth, brain drain (1990's):
https://en.wikipedia.org/wiki/South_Africans_in_the_United_K...
According to the 2001 UK Census, 140,201 South African born people were calling the UK, although most recent estimates put the population (including those of South African descent) at over half a million. Unlike South Africa itself...The 2001 census showed that 90% of South Africans in the UK are White
(3) Objective measures of Violent Crime:
UNODC murder rates most recent year
South Africa 31.8 / 15,940
UK 1.2 / 722
But to the broader point also for context:
Subregion Rate Count Region
Southern Africa 30.5 17,484 Africa
Central America 28.5 44,997 Americas
Eastern Africa 21.9 69,344 Africa
Middle Africa 20.8 25,330 Africa
South America 20 79,039 Americas
Northern Africa 5.9 12,276 Africa
Northern America 3.9 13,558 Americas
Western Europe 1 1,852 Europe
Australasia 1 268 Oceania
SA is basically an ~order of magnitude more violent that north america or western europe base on these data. Furthermore, the variation withing the African data from the sub-saharan regions to the north african ones is quite discernable.