Desire is the motive force, that which leads us toe self development and growth. Only that desire has to be in the limits of her mar morality or ethics. For one, when one oversteps the limits of morality because i just can't control either fear or temptation. Some people commit crimes out of terror, some mis ther they can't face it, or out of temptation. Crisna says, yes, i am even desire, but that is which is within the limits of dagma.