Are all pyromaniacs/ arsonists destined to be serial killers or likely to harm others?

It seems like a common crime stereotype that pyromaniacs and arsonists will become serial killers. here are my questions.

1. Do all pyromaniacs/ arsonists harm or kill people?

2. Do those who like setting fire for fun harm or kill people?

3. Are pyromaniacs insane and can they still have a normal life?

Thanks!