Why does bootstrap use the class 'form-group'?

Why does Wufoo use li tags for each field?

The people you should be asking these questions are the authors of these frameworks.

Enclosing related form elements into fields would add clarity.

You can do this easily enough with the standard elements as they are now. A fieldset allows you to group multiple inputs. The label tag can be used to tie an input to its description.

Every major front-end framework has some class or tag to differentiate each field.

This is because each framework has a specific approach to styling these fields and no matter what standards you come up with, people will keep inventing their own ones... which leads us to the point...

Why the heck don't we have a single HTML tag to bring some normality to form design?

Because HTML tags are not about design. HTML is supposed to represent content, the structure of information and not how something looks. Apparently, the people responsible for the development of the standard consider the current state of the language sufficient in this matter. Web designers are given a lot of freedom as to how to style these elements with CSS as well as to use additional elements around them, which is exactly what you observed.

To sum up, design is not what the language is about. Semantics are the core of the specification. If you ever try to standardize designs, there's only one way this can turn out. Randall Munroe from XKCD makes an excellent point about this phenomenon:

Why does bootstrap use the class 'form-group'?

Why does Wufoo use li tags for each field?

The people you should be asking these questions are the authors of these frameworks.

Enclosing related form elements into fields would add clarity.

You can do this easily enough with the standard elements as they are now. A fieldset allows you to group multiple inputs. The label tag can be used to tie an input to its description.

Every major front-end framework has some class or tag to differentiate each field.

This is because each framework has a specific approach to styling these fields and no matter what standards you come up with, people will keep inventing their own ones... which leads us to the point...

Why the heck don't we have a single HTML tag to bring some normality to form design?

Because HTML tags are not about design. HTML is supposed to represent content, the structure of information and not how something looks. Apparently, the people responsible for the development of the standard consider the current state of the language sufficient in this matter. Web designers are given a lot of freedom as to how to style these elements with CSS as well as to use additional elements around them, which is exactly what you observed.

To sum up, design is not what the language is about. Semantics are the core of the specification. If you ever try to standardize designs, there's only one way this can turn out. Randall Munroe, the author of XKCD makes an excellent point about this phenomenon:

Why does bootstrap use the class 'form-group'?

Why does Wufoo use li tags for each field?

The people you should be asking these questions are the authors of these frameworks.

Enclosing related form elements into fields would add clarity.

You can do this easily enough with the standard elements as they are now. A fieldset allows you to group multiple inputs. The label tag can be used to tie an input to its description.

Every major front-end framework has some class or tag to differentiate each field.

This is because each framework has a specific approach to styling these fields and no matter what standards you come up with, people will keep inventing their own ones... which leads us to the point...

Why the heck don't we have a single HTML tag to bring some normality to form design?

Because HTML tags are not about design. HTML is supposed to represent content, the structure of information and not how something looks. Apparently, the people responsible for the development of the standard consider the current state of the language sufficient in this matter. Web designers are given a lot of freedom as to how to style these elements with CSS as well as to use additional elements around them, which is exactly what you observed.

Why does bootstrap use the class 'form-group'?

Why does Wufoo use li tags for each field?

The people you should be asking these questions are the authors of these frameworks.

Enclosing related form elements into fields would add clarity.

You can do this easily enough with the standard elements as they are now. A fieldset allows you to group multiple inputs. The label tag can be used to tie an input to its description.

Every major front-end framework has some class or tag to differentiate each field.

This is because each framework has a specific approach to styling these fields and no matter what standards you come up with, people will keep inventing their own ones... which leads us to the point...

Why the heck don't we have a single HTML tag to bring some normality to form design?

Because HTML tags are not about design. HTML is supposed to represent content, the structure of information and not how something looks. Apparently, the people responsible for the development of the standard consider the current state of the language sufficient in this matter. Web designers are given a lot of freedom as to how to style these elements with CSS as well as to use additional elements around them, which is exactly what you observed.

To sum up, design is not what the language is about. Semantics are the core of the specification. If you ever try to standardize designs, there's only one way this can turn out. Randall Munroe from XKCD makes an excellent point about this phenomenon: