NI6210 Counter, Sample rate and loop time

I was trying to make a counting task by 6210.

Counter setting Dev1/Ctr0; Input (1KHz) to DEV1/PFI0; sample clock Dev1/PFI2, generated from PFI5.

If I set sample rate 500, sample per loop  500, number of loops about 100. The task will finish about 10s, with all counts 0.

My question:

1. why the taks take 10s to finish, I suppose it should take 100s, as the time would be "sample per loop" / "sampel rate" * "loop number".

2. why I didnot get any counts