What if someone said it isn't impossible, but there are big challenges, and based on your skill set, you're likely to fail. It is those kinds of non-glorified situations where perseverance is crucial, but it can also lead to spectacular failure.
Isn't the point that "unlikely" is a vague (with negative innuendo)?
...and that a more rational approach is to say, "The value of a possible success" is high enough that it's worth the expenditure of energy to bet the "losing" side of a p = .01 (or whatever)".
[of course it's going to depend on who is expending the energy - and who get what portions of the possible success benefits]
