Relentless portrays anger and selfishness as an inherent part of being a competitor. Grover argues that Cleaners are always in control of their emotions and do not allow themselves to become distracted by their own feelings. However, he also believes that a controlled “simmering” anger can be a useful fuel, motivating Cleaners to succeed. This relates to his arguments about Cleaners’ “dark side,” which he defines as “the part of you that you don’t show anyone else, the part that refuses to be taught, refuses to conform and behave” (69). For example, a person who has lost their job might channel their frustration into proving themselves qualified for another, while someone angling for a promotion might lean into a sense of rivalry with their coworkers. Overall, Grover’s message is that the road to success requires people to unapologetically embrace the angry or dark part of themselves.

Grover argues that people can consciously choose the effect that pressure will have on them. If they conceive of it negatively, Grover argues, they will suffer its detrimental effects. However, if they consider it a useful challenge or fuel, it will propel them to success. As he explains, “Stress is what brings you to life” (98). In practice, this means both reconceptualizing external stressors as opportunities and applying pressure to oneself when no one or nothing else will. The former could mean recasting an injury or illness as a chance to build a healthier lifestyle, while the latter might look like creating new challenges for oneself in a job that has become routine (setting personal deadlines, taking on additional tasks, etc.). The point is to stop trying to avoid or minimize stress and instead embrace its role in one’s journey toward achievement.

In Relentless, Grover argues that most elite performers do not aspire to a single goal but to continued excellence. While Closers may celebrate one achievement and feel satisfied, Cleaners are determined to remain the best at what they do. As a result, they have no “finish line” but instead work to maintain or even build on their excellence. The author points to Michael Jordan as an example. Immediately after winning the championship, Jordan would begin strategizing his next victory. Grover recalls, “We’d be back in the locker room, champagne dripping down the walls, and he’d already be telling me what we needed to work on for the next season” (27-28). Though Grover frames this advice largely in terms of sports, it is applicable even in the realm of personal relationships, where readers might seek to avoid complacency by continuously finding new ways to show their love and commitment to a friend, partner, relative, etc. Across all areas of life, what most distinguishes Cleaners from other high achievers is their commitment to not only becoming, but remaining, the best at what they do.