WordNet sense 1 (a state of extreme poverty or destitution):

indigence, pauperism, penury, pauperization

WordNet sense 2 (a condition requiring relief):

demand

WordNet sense 3 (anything that is necessary but lacking):

want

WordNet sense 4 (require as useful, just, or proper):

ask, involve, necessitate, postulate, take, require, postulate, call for

WordNet sense 5 (the psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior):

motivation, motive