Why sell me a faulty phone

This morning I phone the manager, Brian and explained how my phone I had bought from them went in for repairs 3 times before and now the screen also went off. I told him it was with Vodacom and now the screen is cracked which I never saw when I took it in. He just kept telling me that they never have problems with their phones and never get 'comebacks' and now that the screen is broken there is nothing he can do. Not interested. He did not even bother to take my name or phone number or look up when I had bought the phone, or if he could assist and phone Vodacom. Nothing, nada, niks, nil, zero. Such is service nowadays in SA.