Security Updates -- Are they necessary in Linux for user?

[Benjamin Sher]

Dear friends:

After installing Fedora and rebooting, I found myself facing the task of 
installing 213 security updates with Update Manager. It took nearly 2 
hours to download and install them. Since I am the only one using my 
Linux OS (as a user, of course), why do I need to worry about security. 
Am I not protected by the root/user system. What's your opinion? Please 
advise.

Thank you.

Benjamin