Recently, I met a devout Buddhist, a kind person who devotes herself to charity work, including hospice care. She believes in karma ~ whatever she does in this life will bring upon results, good or bad, in this life or her next reincarnation. Not to be uncharitable about it, I'd say that the motivation is basically self-centered. Christians love others because they love God out of gratitude for his love ~ an entirely differently-directed motivation.
There are lots of unloving people around, but I do see that everyone has the potential of becoming a great lover because God is love. Anyone who is open to this love will be filled by this love and transformed into a loving (and happy) person. The absolute truth.