Purpose of duplicate css dest?

[bas72]

Could someone please explain what the purpose of the duplicate destination for the css task is?

  .pipe(gulp.dest('_site/css'))
  .pipe(browserSync.reload({stream:true}))
  .pipe(gulp.dest('css'));

What benefit is there of copying files to ./css for 'future jekyll builds' as well as directly to the _site/css directory?

[HaoZeke]

Live reloading. Means your sass changes don't trigger a new jekyll build.

Has a HUGE speed benefit.