Dear (Name), We are always looking for ways to improve at (company name), and I would like to request your feedback on our latest project/service etc. Your opinions matter to us and your feedback is used to improve how we work and ensure we deliver a consistently high-quality service.
How do you request feedback?
First, ask permission
I'd really appreciate if I could get your feedback on my performance. I want to improve, and I know your feedback will help me do that. Make it clear that you have specific skill areas that you'd like feedback on, as well as being open to their suggests regarding development focus.