Allo User
Whether you need the new drivers depends on several things:
1} What do you do on your PC?
2} Is anything running slow - keeps stop/starting - crashing - generally misbehaving?
If Q1 is basic things like word-processing, emailing, browsing the web etc., then it's unlikely you need any driver updates, unless the answer to Q2 is yes, too.
If Q2 is yes to anything, then you need to update your drivers.
As Aryeh mentioned above, the manufacturers release new drivers when the existing ones are known to either contain bugs or clash with certain software on the PC or sometimes, when the new drivers are more effective at what they do - slimmed down, run more efficiently and so on.
At the same time though, as The Doc pointed out - If the PC's working fine and behaving itself, don't try and fix what ain't broke
Usually, updating drivers is a piece of cake, they install with no problems but, there's always an occasional time when updating them can cause more problems than they're worth. It's a bit of a fine balancing act really.