Great question. A design strategy is one that uses design to help a business win.
Great design strategy shows how design can make your product stand out, work better for users, and maximise value, all while supporting your business goals.
A design strategy makes sure that design is a valuable asset for the business right from the start, not as an afterthought.
It mixes understanding customers, knowing what can be made, and business smarts - making sure that what you create looks good, works well, and hits the right note with the people you want to buy it, helping your business grow.