Perhaps this was another useful quality for soldiers-though again, it didn't seem to have kept him out of trouble before.
"I can't think of any quality more useful than a little innocence."
They have other unusual qualities, quite useful in our cause.
Over the years, he had found it a useful quality.
That was a useful quality, sometimes, in a military leader.
So, to the extent that they can, that is a useful quality.
Patience and quiet assurance are useful qualities in his job.
This is a useful quality in any dry climate, warm or cold.
They would certainly have noticed it, but there are other qualities useful to a sovereign.
They value things directly because of their useful qualities.