ひゃくがいあっていちりなし

百害あって一利なし

表記・読み：百害あって一利無し・ひゃくがいあっていちりなし

1. 1

   all pain, no gain; doing no good and a lot of harm; having no redeeming features; being a complete disadvantage; a hundred harms and not a single gain

   expressions (phrases, clauses, etc.)idiomatic expression