The mistake happened when I unintentionally snapped a photo while moving my camera.
The mistake happened when I couldn’t focus anything.
The mistake happened when I tried new techniques too many times without knowing the real effect such as this multi-exposure function.
The mistake happened when I photographed through window and got the reflection of my dad on the sky out there.
The mistake happened when I shouldn’t have put something under/around/near the subject and the sights of them drew the attention to themselves.