That you need to run 'lilo' after doing any change to the bootloader configuration or a kernel update or change. Grub doesn't need that.
Grub can read directly from the filesystem, so it can read the menu and other files directly during boot. On the other hand, lilo can not do that, it needs a map to find those things it needs being compiled before hand (by running the 'lilo' command).
Just to concur with Carlos, after any kernel upgrade, you'll need to run "#/sbin/lilo" to update Lilo's boot selection. There is plenty of documentation for lilo and it is easy to update and modify. It may lack a few of the functions that Grub supports, but it works well enough. You won't be disappointed. Besides, after you make any changes you need or want, you won't need to tend to it again. ~James