Why should I fix E_NOTICE errors?

Question

As a developer, I work with E_NOTICE turned on. Recently though, I was asked why E_NOTICE errors should be fixed. The only reason that I could come up with was that it is be

Answer 1

Often they're indicative of logic errors or typos. They'll help you spot situations where you've mistyped a variable name or are trying to use a variable before it's been set.

I've also seen arguments that it's more efficient to avoid errors