why does "make install" write to files outside of DESTDIR ?

[Eitan Adler]

Steps to reproduce:

rm -rf /srv/www/devbox/
mkdir /srv/www/devbox/
env DESTDIR=/srv/www/devbox/docs/docs make -s all install

Expected behavior: no files are written to outside of /srv/www/devbox/docs/docs
Actual behavior: /srv/www/devbox/articles and /srv/www/devbox/books exist

Why is this? Is there some way to avoid this?

-- 
Eitan Adler