Rewrite the following sentence in a more concise way.
Although he had been studying for several hours he had not finished the task.
He hadn't finished the task despite studying for hours.
Complete the following task based on the instruction and optional input provided.### Instruction:
Rewrite the following sentence in a more concise way.

### Input:
Although he had been studying for several hours he had not finished the task.

### Output:
He hadn't finished the task despite studying for hours.