Serena Willams became the latest athlete to announce that she wouldn’t be competing at the 2021 Summer Olympics in Tokyo on Sunday night. The night before the 2021 Wimbledon Championships, which began on Monday, Williams sat down with reporters and explained: “I’m actually not on the Olympic list,” she said during the video conference. “Not that I’m aware of.”

“There’s a lot of reasons that I made my Olympic decision. I don’t really want to — I don’t feel like going into them today. Maybe another day,” Williams stated. “In the past, [the Olympics have] been a wonderful place for me, but I really haven’t thought about it, so I’m going to keep not thinking about it.”

Williams, who is a four-time gold medal-winning Olympian, made the announcement that she is stepping back from the Olympics after a number of other prominent athletes — including other tennis stars — confirmed that they would not be participating in the Tokyo games, either. Rafael Nadal, who has won two gold medals at the Olympics, announced that he would be skipping the summer games, as well as Wimbledon this year. American men’s singles players John Isner and Reilly Opelka have also announced their decision to forgo the Tokyo Olympics, and male players Casper Ruud, Denis Shapovalov, Roberto Bautista Agut, Cristian Garín, and Dominic Thiem are joining them.

Outside of tennis, the list of athletes passing on travelling to Tokyo continues to grow: equestrian Eric Lamaze of Canada, swimmer Pieter Timmers of Belgium, basketball player Andrew Bogut of Australia, and all of North Korea’s athletes are among the people and teams who are sitting the competition out. The question now remains: Why are so many athletes skipping this year’s games?

As with any personal decision, the answers vary. For some athletes, the Olympics being postponed for an entire year pushed them into early retirement.

“I would have made this decision earlier if it wasn’t for the postponement of the Olympics,” Andrew Bogut told listeners on his podcast, Rogue Bogues. “I was hoping to get to [the] 2020 Tokyo Games and then calling it a day after that. I just can’t physically and mentally get to 2021 with the way the body has been.” Pieter Timmers also cited the year gap between the initial games and the rescheduled competition as his reason to not compete and announced that he would retire at the end of the season.

For other athletes, the COVID-19 virus still spreading was a reason not to travel and compete. The country of North Korea cited the pandemic as the reason for their lack of participation. And Eric Lamaze said in a statement last month: “My health is something that I take very seriously, and I’ve decided that Tokyo is not the best venue for me.”

As for some athletes, like Williams, deciding not to compete at the Tokyo Olympics remains a personal and private decision. (Williams stated that she wouldn’t be speaking on the matter any further, and can now focus on the 2021 Wimbledon Championships.)

Refinery29 has reached out to the International Olympic Committee for comment. We will update this report as we know more.

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