When you need something, you need it in order to be fully you or in order to operate at your best. A want is simply something that provides gratification, usually temporary. If it's a need, GET THE NEED MET, even if it makes no sense. Generosity as a By-product vs Generosity as a Focus. The more selfish you become, the more generous you will naturally be.
Most folks try to be generous first before they've become selfish enough.
Mistake, because it's usually not sustainable, or if it is, it's highly costly to you, your life and those around you. Wants vs Shoulds. A want is something that you acquire that makes you feel good. Some people don't think they 'should' be THAT selfish. Joy vs Pleasure.