JSFiddle - React, Tailwind, and code Playground

HTML

<div id="log1">
    <p>(Return 0- NOT exiting the loop)</p>
</div>
<div id="log2">
    <p>(Return false- exits correctly)</p>
</div>
<div id="log3">
    <p>(Return 0- exits correctly)</p>
</div>

CSS

#log1 {
    border: solid 1px red
}

#log2 {
    border: solid 1px green; margin-top: 20px;
}

#log3 {
    border: solid 1px blue; margin-top: 20px;
}

JavaScript

var alpha = ['a','b','c','d','e','f'];

$.each(alpha, function(i, val){
    if(val == 'd'){
        $('#log1').append('Exit (return 0)'+'<br/>');
        return 0;
    }
    
    $('#log1').append(val+'<br/>');
});



$.each(alpha, function(i, val){
    if(val == 'd'){
        $('#log2').append('Exit (return false)'+'<br/>');
        return false;
    }
    
    $('#log2').append(val+'<br/>');
});

for(var i = 0; i < alpha.length; i++) {
    if(alpha[i] == 'd'){
        $('#log3').append('Exit normal forloop (return 0)'+'<br/>');
        return 0;
    }
    $('#log3').append(alpha[i]+'<br/>');
}