Kyrgios has openly said that he "does not love tennis" and has a greater interest in basketball. He openly critiqued his dedication to the sport after his exit at the 2017 US Open to fellow Australian John Millman, saying that he is "not dedicated to the game at all" and "There are players out there that are more dedicated, that want to get better, that strive to get better every day, the one-percenters. I'm not that guy." At the 2015 Wimbledon Championships, after he failed to return numerous serves, Kyrgios was accused of tanking—deliberately not playing up to his abilities—during the second set of his fourth-round loss to Gasquet. Kyrgios was booed by the crowd for his perceived lack of effort, but denied the accusations, stating "of course I tried".
In October 2016 Kyrgios was fined $32,900 (on top of an earlier fine of $21,659—$13,127 for lack of effort, $6,563 for verbal abuse of a spectator, and $1,969 for unsportsmanlike conduct) and banned for eight weeks for "lack of best efforts" against unseeded Mischa Zverev in the second round of the Shanghai Rolex Masters. He threw the match 6–3, 6–1, in 48 minutes,[148] at one point asking the umpire: "Can you call time so I can finish this match and go home?" When later asked during a press conference if he thought he owed the fans a better effort, he responded: "What does that even mean? I'm good at hitting a tennis ball at the net. Big deal. I don't owe them anything. If you don't like it, I didn't ask you to come watch. Just leave."
Some commentators believe Kyrgios is more committed than he claims. After a string of successes in 2017, Kyrgios attributed his greater consistency that year to an improved work ethic. He said: "I've made an effort to try and put in the work every day. It hasn't been easy." However, he continues to cause controversy on the court. Hugh van Cuylenburg, founder of the Resilience Project in Australia says Kyrgios is deliberately provocative and thrives when there is chaos around him: “Some people thrive in a hostile environment because it tricks them into the right level of arousal and reminds them of how much they care and how much they want to win – and Kyrgios is one of those.”