Looking at the results of this years Client Survey it appears that Code Quality is not as high up the priority list as it perhaps should be. It's not always obvious just what the implications can be if you don't keep on top of these errors.

When I'm running training sessions and discuss Code Quality I point out that although there is a W3C standard for HTML that browser must abide by, there is no standard for what the browsers should do when they come across non-standard code. Should they ignore it or assume you meant something else ?

The discrepancies between what browsers do under these circumstances is one of the factors that lead to Webpages not rendering in the different browsers - and there's a proliferation of browsers out there especially with the increase in browsers on mobile devices. With all these browsers out there it's becoming more and more difficult to ensure that your Webpages work across all browsers.

A key way to help with this, though it's not the only thing, is to ensure that all of your code is compliant with the W3C standard.

I came across an example yesterday of a Webpage that was completely jumbled by IE8 (including when I tried viewing the screen in "compatibility mode") yet when I viewed it in Firefox it was fine. It was a real simple coding error where they'd try to put a couple of words in the Meta Description in double quotes.  This made all of the words after the first double quote (double quote is the delimiter for the Description) to be treated as Attributes, which meant they were all errors.

Here's what it looks like:

Clearly something that would have been spotted if the editor had viewed it in IE.

If they'd have checked the page with Snapshot they'd have had the error clearly pointed out to them both in the Page View and the Source View ==>