In an ideal world every device or technology world work perfectly fine with each other out-of-the-box. Unfortunately in the real world things are never that easy: manufacturers keep releasing devices that don't work how you'd expect them to, obscure Command Classes are used or have functionality implemented in such a way that specific support needs adding to the Controller to allow you to use the device fully or simply because there are dozens of different technologies to choose from but no standard to make them “talk” with each other.
This often means hours of research and trial-and-error on an effort to simply make “X do Y”, something one might have expected it would just take a minute. We know how despairing that is – we go through the same grief on a daily basis!
This doesn’t seem to bother most manufacturer which keep releasing devices without providing detailed information or to make sure they are fully compatible with mainstream controllers. Thankfully once in a while we see someone who actually cares and release useful technical details and guides to help their customers.