expression, noun
youthful indiscretion; youthful excess; youthful enthusiasm
A set phrase used to excuse or reflect on foolish or excessive behavior done out of youthful passion or inexperience. Often used with a self-deprecating or forgiving tone.
若気の至りで、あんな無茶をしてしまった。
It was youthful indiscretion that made me do such a reckless thing.
あの失敗は若気の至
That mistake was just youthful excess, and now it's a funny story.