きっかけ

Common patterns

• 〜をきっかけに: triggered by ~, taking ~ as an opportunity
• 〜がきっかけで: because of ~, ~ being the trigger
• きっかけになる: to become a trigger/catalyst
• きっかけを作(つく)る: to create an opportunity
• 〜を始(はじ)めたきっかけ: what prompted one to start ~

Nuance: きっかけ is neutral — it can be used for both positive and negative outcomes. It focuses on the initial trigger or catalyst, not the direct cause. Often used in self-introductions and interviews when explaining why one started something.