Maybe you use a product heavily or you have a lot of industry knowledge in one area, so you can choose to leverage this existing understanding to improve products you interact with or you know well.
You can find some examples here and here.
<aside> 💡 Remember: if you’re going for a redesign make sure you actually solve a problem you identify and validate, and not just set out to make a prettier screen. UX is about value and function, so you want to work on making products more usable, not just better looking.
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