Used when you don't know the answer and feel it is impossible to find out.

Expressing Uncertainty

Highlights that the reason or cause is a mystery to everyone.

Emphasize Mystery

Suggests that only a higher power or God could understand or know the answer.

Shows you are confused and cannot rationalize the situation or behavior.

Can convey a sense of exasperation with the inexplicable nature of something.

Use when the future or result is unpredictable or impossible to guess.

Prefaces a guess about an unknown situation, emphasizing its speculative nature.

Used to underscore that specific details are not known or are unknowable.