Why do so many footballers go bankrupt?

“It was the brown envelopes that kept falling through the letterbox that filled Dean Windass with foreboding. Windass was a spiky but effective striker whose 18-year senior career had taken him through all four divisions, including spells in the Premier League with Bradford City, Middlesbrough and Hull City, plus the Scottish top flight with Aberdeen. While he was never one of the game’s superstars, he had earned good money at a time when English football was booming. …”
NY Times/The Athletic