How did capital controls limit cash withdrawals in Greece during the 2015 financial crisis?

During the 2015 financial crisis, the government led by Prime Minister Alexis Tsipras implemented capital controls in response to the European Central Bank's refusal to increase emergency liquidity assistance to Greek banks.12

To prevent a total financial collapse, the government ordered the closure of the country's banks and suspended trading at the Athens stock exchange. As part of these measures, cash withdrawals from automatic teller machines were strictly limited to €60 per day until a national referendum on bailout terms could be held.12