To be immensely sure of what you want is probably as dangerous as it is to be completely unsure.
There should be no doubting the dangers of forging ahead without the compass that is resolve; for if we do, what end, what shores, what treasures that await us at the close of our journey shall be but an edict of chance alone. We could end up on a island full of glistening gold or one full of weeds and poisonous thorns.
On the other hand, should our resolve be so great as to command even the waves that carry us, there might be bred in us a diaphanous fear of coming to a realization that we have all along been on the wrong course, and that our compass is as flawed as can be our perception. It is when we feel so certain of what we want, and have as such set ourselves on a particular course, that should our decision be challenged by adversity, or our esteem be beaten by transient failures, we would immediately begin to doubt our capabilities. It is the fear that arises from an excess of zeal, a fear that in spite of our steadfast confidence, we are actually, foolishly, wrong. And it is precisely this fear that inflates any setbacks we might encounter, creating tall threatening tidal waves out of the occasional turbulence.
The danger of being resolved is hence no less potent than that of straying unresolved. While irresolution may well land you in miserable regret, resolution threatens to shrivel the confidence you have in yourself, leading you to ultimately doubt the authenticity of your capabilities, talents and worth.
But what if one really were in the right direction? Conversely, what if one were really in the wrong direction? It is hard to be certain of anything when we are so easily deceived by our passions and pride. But let never forget our passions, for they are eternal within us, and the rest we ought to simply leave to God.