The phrase "are lenient" means being understanding, forgiving, and not strict in one's approach. The antonyms or opposite words for this phrase would be harsh, strict, rigid, unforgiving, and uncompromising. A person who is not lenient is someone who is tough, relentless, and unyielding. They impose rules and regulations strictly and expect others to follow them without any exception. A non-lenient approach is essential in some situations, especially when it concerns safety, discipline, and security. However, in most cases, leniency and flexibility can promote teamwork, creativity, and innovation. Therefore, it is crucial to balance leniency and strictness according to the context and the desired outcome.