Strange it is, indeed... as others explained, end must be greater than start. You could use negative values to count down:

perl -e 'for (-5..-1) { print -"$_\n" };'
+5
+4
+3
+2
+1
[download]

Leading pluses? Eh. That seems to be perl's way of saying it knows that double negation is affirmation... how strange... but on a second look, one learns that it has to do with the string resulting from the interpolation:

perl -e 'for (-5..-1) { print -$_,"\n" };'
5
4
3
2
1
[download]

A stringified number and a number-number are not always the same thing.. ;-)

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}