Sick of developing a user interface for mobile, then doing it again for desktop, then again for tablet? How about including features that make sense on a smaller device, but not on a larger screen? Or what if you want the layout of elements on the screen to change based on screen size and device type? Get familiar with the Adaptive UX patterns, features and elements of the Windows 10 Universal Apps, and it will make your developer life more about features, less about plumbing (and avoiding losing those last few hairs on your head).