That end tags were an option and not mandatory was a feature of the SGML language that HTML was based on. I'm not sure specifically if this was allowed in the d

That end tags were an option and not mandatory was a feature of the SGML language that HTML was based on. I'm not sure specifically if this was allowed in the description for the P tag, however I suspect it is. So this was entirely by design and probably not all that difficult to implement. That it might not be appealing to some I can understand. I suspect the creators of SGML had very different concerns. I like that HTML has a very humane interface.