Design is an artistically creative process. Takes talent, I wouldn't hire a designer if I don't perceive the work they've made as beautiful.
But hiring an engineer, there are certain things you can overlook in favour of their capacity to actually build something. I can overlook their code quality, but only because we have a boarding process in which one of the things we make sure a new engineer understands is our quality standard in writing code, the systems we use to enforce that standard from code reviews to pre-commit hooks and lint checking.
An engineer has the capacity to adapt to these changes of both quality and process.
IMHO, you can't teach a designer who isn't talented how to make beautiful things. Albeit beauty is subjective, but there's still a common ground upon which the majority will perceive this piece of art work as beautiful.