Why are the psychological forces that stop us from attaining Nibbana greater/stronger than those propel us towards Nibbana?
Instinct (refer to  AN 7.11). The Earth today has 7.7 billion people plus zillions of animals, insects, fish &amp; other life forms. This whole Earth is created by lust &amp; craving (refer to SN 12.44). Basically, each creature is born from reproduction for the purpose to further engage in reproduction. It goes on &amp; on like this, endlessly for the unenlightened (refer to SN 15.1), until the Earth burns up.