Only when all conditions have been satisfied do we reach the command, in which case the form will be submitted.
You'll see that the all validation scripts presented on this and subsequent pages adhere to the same basic format.
The illustration below shows this relationship: Note that the 'I' in selected Index needs to be capitalised - Java Script functions and variables are always case-sensitive. Read more about the humble checkbox in our HTML5 Checkbox Validation article.
Radio buttons are implemented as if they were an array of checkboxes.
To take things a step further you can even explore Ajax Form Validation which lets you supply real-time feedback using server-side scripts triggered by Java Script events.