What is the reason for the increase of potholes on South African roads?

JOHANNESBURG – This week, we turn our focus on the state of roads nationwide according to Sanral, there’s been a 67-percent increase in potholes over the past five years.
Last week, the Mbokodweni River bridge in KwaZulu-Natal partially collapsed, leading to the closure of the N2.
READ: Buffalo City Metro’s pothole backlog
What is the reason for the poor condition of South Africa’s roads and bridges?
Gundo Maswime, a civil engineering lecturer at the University Of Cape Town discussed this with eNCA.