逆効果

1. Origins, structure, and basic meaning

• Structure: 逆効果 is read ぎゃくこうか and means an effect opposite to the one intended.
• Basic usage: It is used when, for example, excessive pressure meant to speed someone up instead makes the situation harder.

2. Common pitfalls and similar expressions

• Compared with 効果がない
  • 効果がない means the desired effect was not achieved, while 逆効果 means the result instead worked against the intended goal.