Java is a very safe language, in that when you do something wrong, you get a relatively clear indication of what you did. If you attempt to access beyond the bounds of an array, or do anything else wrong, you get an immediate and diagnostic failure. If you lose all references to an object, it gets cleaned up by the garbage collector. There's no way to attempt to access inaccessible or unallocated memory.

Not so with C. A C program will happily access beyond the bounds of an array, possibly resulting in an immediate crash of the program (with little hint of where it was when it happened), no effect, or a delayed effect, as corrupted data is only detected later when accessed. Dynamic memory management is under manual control, and if you forget to deallocate something, the memory is wasted until reclaimed when the program exits. It's also very easy to deallocate memory, but continue to use it accidentally, again with unpredictable results.

In C, these activities require greater responsibility from the programmer.