DATEDIF function existence

[Sektor]

I know that since Excel 2002 this function doesn't appear in functions list and there's no help about it.
But what is strange is that DATEDIF appears in official ECMA-376 specification - in first, second, and third editions.
The description of this function can be found:
1-st Edition - Part 4, page 2601
2-nd Edition - Part 1, page 2393
3-rd Edition - Part 1, page 2400

 

[Aladin Akyurek]

I know that since Excel 2002 this function doesn't appear in functions list and there's no help about it.
But what is strange is that DATEDIF appears in official ECMA-376 specification - in first, second, and third editions.
The description of this function can be found:
1-st Edition - Part 4, page 2601
2-nd Edition - Part 1, page 2393
3-rd Edition - Part 1, page 2400

The function does till exist in Excel, but just not listed in the All category of Insert Function and undocemented. The reason is unknown. Comparing it with YEARFRAC might provide some clue.

 

[Sektor]

Then I don't understand rationale of hiding it in UI but exposing it in specification.

 

[Aladin Akyurek]

Then I don't understand rationale of hiding it in UI but exposing it in specification.

How about not encouraging its usage, albeit indirectly?