expression, godan verb (-ru)
backfire; have a harmful result
Used when an action intended to help or be positive ends up causing harm or trouble instead. Often implies an unintended negative consequence.
親切のつもりが仇になって、彼を怒らせてしまった。
My attempt to be kind backfired and ended up making him angry.
過保護
Overprotectiveness had a harmful result, and the child became unable to be independent.