Kernel updates are essential is Linux distros to get and enjoy awesome new features. Kernel updates tend to add new features and drivers as well as fixing problems on the old one’s and a few bug fixes along the way… It’s beneficial to update your kernel although you dont HAVE to.
Frequent updates may not always be an advantage but as far as security goes, it is. If some kind of weakness is found in the kernel it could potentially be used to compromise the system until it is fixed. So it’s best if as little time as possible passes from the discovery of a security hole until it’s been fixed. There’s really no reason to wait and leave an open security hole while there’s a perfectly good fix available.
It’s good to always have the latest kernel. Even if there’s no security problem, an update might fix a bug or improve stability. And of course, new features are nice.
Sometimes kernel updates disable some hardware. Recently I updated to the latest Linux kernel and Fedora stopped to show me WiFi and Mobile broadband devices. Fortunately most Linux distros keep all the kernels, and we can boot from another old kernel via GRUB and remove the new kernel.
We can remove kernel with
sudo yum remove kernal
and we can check the kernel we are currently using by