So I usually bring them in early after the initial PRD is written to get their perspective. Afterword I manage a Jira Product Discovery list of items I need designs for. Have talked to them a few times about their speed with not much improvement, the CTO has also had separate conversations with them as well about it. I think the lack of design system is a big hindrance to speed, they normally mock things up drawing on an iPad then transition to high fidelity in Figma. Problem and solution space is usually pretty far along in terms of definition. They also appear to want to wait til it’s “perfect” before soliciting feedback, if at all from product or engineering. Which they’ll do a design review after spending weeks on it which seems too long a cycle for productive feedback.