Love fails for many reasons. Lack of communication is one. Poor communication or inability to express needs wants, and emotions can lead to misunderstandings and resentment in a relationship. Another reason is incompatibility. Differences in values, interests, or life's goals can create conflict and make it difficult for a relationship to thrive. Also, trust issues. Trust is a fundamental aspect of a healthy relationship. if trust is broken, or there are constant doubts and insecurities, love can fall.