At 43, Tom Brady made NFL history winning his seventh Super Bowl title and fifth Super Bowl MVP award when his Tampa Bay Buccaneers defeated the Kansas City Chiefs in Super Bowl LV on Sunday.

But Brady has said he isn't driven by such records or accolades — instead his motivation comes down to one question: "the coulda/shoulda question," Brady wrote in his 2017 book, "The TB12 Method: How to Achieve a Lifetime of Sustained Peak Performance."

"If I don't play my best, why I am disappointed? Because I coulda, shoulda played better, done better, worked harder, prepared more," he wrote.

For Brady, whether it's effort, execution or mindset, it's all about knowing he put in his best effort, win or lose.

"I wish every season ended in a win, but that's not the nature of sports (or life)," he wrote on Instagram in January 2020 after missing his chance for a seventh Super Bowl win with the New England Patriots. "Nobody plays to lose. But the reward for working hard is just that, the work!!"

Winning, breaking records and the accolades, "[t]hose things have honestly never mattered to me," Brady wrote in his book.

Instead, "it's always about what I can do better in the future. That journey is never-ending. In many ways I don't think I'll ever be satisfied," he wrote.

In his book, Brady also quoted the late NCAA basketball coach John Wooden: "Success is peace of mind, which is a direct result of self-satisfaction in knowing you did your best to become the best you are capable of becoming."

This story has been updated with information on Super Bowl LV.

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