What is the reason for breaking a suspension of a car?
to break something would be unlikely without some type of abuseive driving , such as slamming the car over curbs and being hard on it in general. It depends on what broke and what you are talking about. with no information this is about all you will ever get on yahoo answers. There is always more to the story.
You have to be more specific on your question, we don't even know if you are asking what causes broken suspension, or if you want a reason to break the suspension of a car. You also dont specify what is broken on the suspension either. But here are most of the culprits for most of the broken suspension parts, Abuse, off-roading, hitting rocks, curbs, or other road obstacles, High speed driving and cornering, improper maintenance and lubrication, aging of components/component fatigue, automobile accidents, and overloading the vehicle.
Lack of maintenance. Most suspension systems that fail happen at the ball joints because the stupid owner never gets under the car to grease them. greasing the suspension is a regular maintenance chore.