Paul Scrivens:

If you have done your time and learned design or coding, then frameworks offer you a great way to take some shortcuts, but only because you know how to tweak your way through them when things get rough. If you are using Bootstrap to quickly get a site out the door, I understand the importance of launching fast and early, but spend a couple of hours making sure your site doesn’t look like the thousand other Bootstrap sites out there.

Nailed it. Bootstrap is an incredible tool that is easily abused by those who see it as a theme. Don’t look at Bootstrap as a coat of paint to slap haphazardly onto your site. See it as a power sprayer that will let you blast through some of the solved problems of front-end code organization so you can focus on the details of the interface.