Wiring rarely fails without warning. Watch for: frequently tripping MCBs, flickering or dimming lights, switches or plug points that feel warm or make a buzzing sound, a faint burning or fishy smell near outlets, discoloured or scorched socket faces, and mild tingles from appliances. Any of these means something is overloaded, loose or degrading.
The most common causes are loose connections, overloaded circuits, moisture, rodent damage and simply old, brittle insulation. Because these faults generate heat, they are a genuine fire risk if ignored — and smoke, not flame, causes most fire injuries, which is why low-smoke HR-FR-LSH wiring matters.
Treat any of these signs as urgent: switch off the affected circuit and have a licensed electrician inspect it. See also how long cables last and when to replace them. When rewiring, upgrading to quality house wires and cables is a worthwhile safety investment.