- If you accidentally push broken code your interactive elements stop working completely. And if that’s a menu for example, your users are screwed
- A lot of these interactive elements use 3rd party libraries which are very heavy, jQuery for example. In a world where mobile device browser share is huge page weight is important
With the ever diminishing share of Internet Explorer 6, 7 and 8 users we can now start making use of more advanced CSS selectors to perform this task.