It is kinda like that. Except you must imagine that sometimes the lock boots you out of your own house and leaves you outside in the rain and never lets you back in till you build another house. Also imagine that you have left the lock open before by accident and all your stuff was still magically still in the house exactly where you left it. Now maybe the fence (firewall) wall was a deterrent, and maybe the barking dog (anti-malware, anti-virus) is the only thing that kept your house from being empty. Look, if updates are working for you, great. If you are having trouble with them and have the energy to sort all that out, great. If they kill your system and you get sick of it, turning them off is not really that big of a deal if you have other security measures in place and avoid stupid programs such as Outlook and the like.