There's a fine line between "doing something else you believe in" and "copping out by abandoning your original commitment." Can we better define the difference between the two? What tips the scales in either direction? And how can you determine which is appropriate in a given situation?
I think the key word here is "commitment." For me, I highly value fulfilling a commitment I've made. Because of this, I would think to complete a commitment first, even though I may no longer believe in it. After I've fulfilled my end of the bargain, so to speak, I'll then move on to the something else that I believe in. For others who might not value upholding their commitments as much, then the standard might be lower to break the original commitment and leave to do the something else they believe in. How does this sound? Does this further inform the original question? Is it too personal? Are there perhaps hard standards that can be applied universally?