Sure we look at a PR's total diff, but sometimes it's nice to look at commits. They're a way to organize your changes. As you know, your changes change as you develop. These changes, however, can be abstracted away so that everyone thinks you write immaculate code. Here's how I do it:
# I'm beginning work on a new poem
echo -e "Roses are green\nViolets are blue" > static/love_poem.txt
git commit -am "writing a new love poem about git"