Resolving Conflicts Between Designers and Engineers

Base the designer's performance on the finished product, rather than the "approved" design on Sketch or Figma. This will hold the designer responsible for things like adjusting designs midway to solve unforeseen problems and working with developers closely to polish the final product.

Too often I've found designers who think their job is done when they hand over the Sketch or Figma file.

Also, designers have a tendency to be very idealistic in their designs because they're designing for their resume portfolio and the judgement of their designer peers. For these designers, you must have a strong product manager to reign in the designs so that they work for the business instead of the designer's resume portfolio.

Lastly, to help designers design for the business instead of their resume, design job interviews should focus more on the goals and constraints of the designs rather than the beauty.