The Bugs
The UNIX manuals are sometimes derided for the BUGS section. 

This is the place where the author(s) of a program list its design
limitations. One UNIX critic said of this policy:
If they know about the bugs, why don't they fix them?

The point is that the early UNIX authors established the beneficial habit
of documenting limits to the program, rather than always letting the end
user find them.

Dennis Ritchie comments:
Every other manual has bugs sections; they just aren't published.

Many of the BUGS sections were intended as pointers for further development
of the programs, rather than as warnings to the user.


Ritchie adds:

Our habit of trying to document bugs and limitations visibly was enormously
useful to the system. As we put out each edition, the presence of these
sections shamed us into fixing innumerable things rather than exhibiting
them in public. I remember clearly adding or editing many of these sections,
then saying to myself "I can't write this," and fixing the code instead.

Ritchie, personal correspondence