Thomas Shey
Legend
Agreed. But to maintain that imprecision I'd say it's on the GM to find a way to describe the odds without using numbers. If the GM has determined the odds are 90% then "There's a small chance you'll blow this but it certainly looks make-able, you've done longer jumps than this before" will do; and if the player wants a clearer definition of "small chance" it won't be forthcoming.
Then unless they know the GM that response means nothing; some people consider 1/3 a small chance, some 1%. The term doesn't have to describe the precise number, but if you're not at least describing a range, you're not really telling anyone anything.