Meaning that When Google releases the Android updates they get released to Nexus devices first since Google supports their own tablets. All other devices get them weeks to months later.

Yes you can root your device and hope someone creates an updated custom rom but what if you just aren't that comfortable with rooting or custom roms? Then you have to rely on the manufacturer. I may be wrong but I think the Sero isn't even running Kit Kat (latest version of Android)yet. (I may be wrong).