...>perldoc -q "quoting"
Found in C:\Perl\lib\pod\perlfaq4.pod
  What's wrong with always quoting "$vars"?
            The problem is that those double-quotes force stringification--
            coercing numbers and references into strings--even when you
            don't want them to be strings. Think of it this way:
            double-quote expansion is used to produce new strings. If you
            already have a string, why do you need more?

            If you get used to writing odd things like these:

                print "$var";       # BAD
                $new = "$old";      # BAD
                somefunc("$var");   # BAD

            You'll be in trouble. Those should (in 99.8% of the cases) be
            the simpler and more direct:

                print $var;
                $new = $old;
                somefunc($var);

            Otherwise, besides slowing you down, you're going to break code
            when the thing in the scalar is actually neither a string nor a
            number, but a reference:

                func(\@array);
                sub func {
                    my $aref = shift;
                    my $oref = "$aref";  # WRONG
                }

            You can also get into subtle problems on those few operations in
            Perl that actually do care about the difference between a string
            and a number, such as the magical "++" autoincrement operator or
            the syscall() function.

            Stringification also destroys arrays.

                @lines = `command`;
                print "@lines";             # WRONG - extra blanks
                print @lines;               # right