According to Rosh in The Bronze Bow, what is Daniel's fatal flaw?

According to Rosh, Daniel's fatal flaw is that he is not
ruthless enough. Rosh tells Daniel,

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"I've warned you before...there's a soft streak
in you. Till you get rid of it you're no good to the
cause."

Rosh had used Joel as
a spy for the cause. Then Joel had been captured, and Daniel and the others are anxious
to get a group together to secure his release. Rosh, however, has no intention of
sending any of his men on a rescue mission. He says,

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"On this mountain every man is responsible for
himself. That holds for Joel...he was stupid enough to get caught. You think I can spare
eight men - or one man - for
that?"

When Rosh coldly
refuses to consider his entreaties to send some men to save Joel, Daniel's eyes are
opened. He sees Rosh, whom he had once idolized, as the cold-blooded, egocentric killer
that he is. What Rosh calls "a soft streak" in Daniel is really a sense of loyalty and
humanity, which is essential in a leader and which Rosh lacks completely. Although Rosh
says that Daniel's "softness" and sensitivity is a fatal flaw, in reality it is a
strength. The fact that Rosh lacks this trait is ironically the fatal flaw in himself
(Chapter 18).