Why web designers should know HTML...

I believe web designers should know HTML even if web designing software is available because of the importance of how HTML affects the process of web making. For example, lets say there might be a glitch in the software, if the designer knows HTML, he or she can go back and fix the mistake because they know how HTML works. Web designers should know HTML because of it's entire usefulness in their job. If a web designer didn't know HTML, it would be like a doctor not knowing the human body and just letting the other staff members and machines take care of the patients.