When a radiator hose breaks your engines coolant will be lost and your vehicles engine will overheat leading to a breakdown or engine damage due to overheating.
The radiator hoses are high pressure hoses that allow coolant to flow throughout your radiator and into your engine and then back out again.
If the radiator hose breaks on you then your coolant will be lost and the coolant will then be pumped out of the engine and radiator and your engine will not be cooled down.
That will result in your engine overheating and your temperature gauge going up.
You'll be stranded on the side of the road with a broken radiator hose and will require replacing them on the side of the road or getting your vehicle towed to a shop.
Always inspect the radiator hoses after 5 to 10 years or 100,000 to 150,000 miles or before setting out on a long road trip.
The radiator hoses should feel firm but not too hard and not too soft either and if you feel a soft spot in the radiator hose then it's going bad and is about to burst on you.
I replace all my radiator hoses every 5 years regardless of mileage and if the hose is still good I keep it in my toolbox or my trunk of my car just to have it as a spare hose in the even one happens to break on me.