The pleasures of prosperity backfired. They bred carelessness and complacency.

繁荣的惬意酝酿了草率和自满，产生了事与愿违的结果。

youdao

I was rather saddened by what he had said and regretted my own carelessness.

我听了他的话心里有点难过，只怨自己太粗心大意了。

《新英汉大辞典》

The driver regretted his carelessness in driving and went to the hospital to say sorry to his passengers.

司机对驾驶时的粗心大意感到后悔，并前往医院向乘客道歉。

youdao

The incident has deepened a feeling of carelessness and hastiness.

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As for Mr Trojan, though untainted by the carelessness and petty scandals that dished the previous team of commissioners led by Jacques Santer last year, the collapse did happen on his watch.

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