Because it is a bloated pile of crap that flags anything that modifies existing code as a virus unless it finds it in its database?
I consider any Norton products made this century malware that needs to be eradicated. I only make an exception for some post 2000 Norton Ghost releases, but by now, they're crap as well.
As someone who fondly remembers the time when Norton Utilities defined "small, efficient and modular" for the kids who had not heard of Unix, I hate what people did to Peter Norton's name.