What is `chattr +x` used for?

The chattr(1) manpage describes the x attribute as:

x      The  'x' attribute can be set on a directory or file.  If the attri‐
       bute is set on an existing directory, it will be  inherited  by  all
       files and subdirectories that are subsequently created in the direc‐
       tory.  If an existing directory has contained some files and  subdi‐
       rectories,  modifying  the attribute on the parent directory doesn't
       change the attributes on these files and subdirectories.

So this attribute is inherited by newly created files/subdirectories, but other than that, the manpage doesn't specify any effect. What is this attribute used for?