BIOS updates aren’t big software upgrades that add new features, security patches, or performance improvements. BIOS updates typically have very short change logs – they may fix a bug with an obscure piece of hardware or add support for a new model of CPU.
If your computer is working properly, you probably shouldn’t update your BIOS. You might end up messing with the BIOS password, too, if you do not know how BIOS works.