First Click and Page Submission Timing are Different, Despite unifying them

I am using a code which emulates the next button upon clicking and selecting a choice in an MCQ question. The timing of the first click should be either similar or ahead of the page submission. However, sometimes I see the submission time is ahead of the first click by up to 100 milliseconds. Below is the code I used. Any thoughts to correct this, please.

Qualtrics.SurveyEngine.addOnload(function()
{
$('Buttons').hide();
var that = this;
this.questionclick = function(event,element){
if (element.type == 'radio') {
that.clickNextButton();
}
}


});