Human Error?

How can you define unlucky?

Today I think I was.
Configuring transceivers today, I was configuring about 10 elements.

Everything fine but a element.

Normally for me, setting only 10 is about one to one and a half hour, but today is different.
Rechecking about 4 times on the same element. Try hard to find the problems.

I can easily blame the devices, but didn't.

In the end I make a table for all device connecting signals to find what the real problems.
Using about 6 hours to see all clear, I find that one station and one receiver defected.

For using that about of time, I think it was my opportunities cost.

At last, I found that I did that all to avoid human error.

And that error should not be me.