unreliable; undependable; indefinite; vague
helpless; forlorn; forsaken
worried; uneasy
彼の返事はどうにも頼り無かった。
His reply was just plain unreliable.
頼り無くて仕事を任せられない人もいる。
There are also people who are too unreliable to entrust work to.
若い頃は頼り無い人物だったが、今は立派なリーダーだ。
He was an unreliable person when young, but now he's a fine leader.