It depends on the engine and by what you mean by "Goes".
On many engines if the cam shaft does not turn as it should with the engine really bad things will happen. Parts that are never supposed to touch each other do and get bent and smashed. What normally causes all this is a broken cam belt. This is easy to prevent by just replacing the belt every so often (say every 50,000 miles) before it breaks.
Cams can also go bad by wearing out. They are supposed to have lumps on them that push the valves open as the cam shaft turns. But if these lumps wear out the valves will not open as they should and the engine will run badly.
On many engines if the cam shaft does not turn as it should with the engine really bad things will happen. Parts that are never supposed to touch each other do and get bent and smashed. What normally causes all this is a broken cam belt. This is easy to prevent by just replacing the belt every so often (say every 50,000 miles) before it breaks.
Cams can also go bad by wearing out. They are supposed to have lumps on them that push the valves open as the cam shaft turns. But if these lumps wear out the valves will not open as they should and the engine will run badly.
