const quotes = '1.lorem 2.ipsum 3.dolor 4.sit 5.amet'.split(' ').sort(_ => Math.random()-.5);

const span = document.querySelector('span');

​

const maxIndex = quotes.length;

let currentIndex = 0;

​

function showQuote(index) {

  span.textContent = quotes[index];

}

​

document

  .querySelector('button')

  .addEventListener('click', () => {

    currentIndex = ++currentIndex % maxIndex;

    showQuote(currentIndex);

  })

;

​

showQuote(currentIndex);