The shoehorning can come from designers who don't put things together using bootstrap components as their design language. Then the developer tries to do forbid

The shoehorning can come from designers who don't put things together using bootstrap components as their design language. Then the developer tries to do forbidden CSS alchemy and go from a Bootstrap component to the designer component. That's using an opinionated framework when your designers don't share the same opinions which often will make things more difficult. Bootstrap and other opinionated frameworks are super handy when you don't have designs/designers though.