Javascript Madlibs Question

I've written out the following code in the workspace but I can't get the counter to go down.:

var questions = 3;

var questionsLeft = '[' + questions + ' questions left]';

var adjective = prompt('Please type an adjective' + questionsLeft);

questions -= 1;

var verb = prompt('Please type a verb' + questionsLeft);

questions -=1;

var noun = prompt('Please type a noun' + questionsLeft);

questions -= 1;

alert('All done. Ready for the message?');

var sentence = "<h2>There once was a " + adjective;

sentence += ' programmer who wanted to use JavaScript to ' + verb;

sentence += ' the ' + noun + '.</h2>';

document.write(sentence);

Honestly not quite sure what to make of it and had a similar issue using += when trying something in an earlier lesson. Any assistance would be appreciated.