Is it beneficial to constantly download these updates from MS?
Is it beneficial to have your car / aircraft serviced on a regular basis ?
Is it beneficial to visit the dentist / doctor once in a while for a checkup ?
Don't tell me it's not the same thing, because it is.
Do you think Microsoft spend millions of dollars on employing people, plus associated infrastructure just to issue these regular updates for fun ?
Honestly ! I can't belive you even asked the question !
Please don't let your computer become yet another botnet member ! If your computer is connected to the internet, you have an unwritten obligation (well, actually, it's probably in your ISP's contract) to do your bit to protect the rest of the internet by taking reasonable precautions. Failing to patch up your computer on a regular and timely basis is just asking for trouble.