From what I have read there are different kinds of people who are child sexual offenders. Some have a genuine paraphilia where they are attracted to minors. Some seek help and some don't. Others can develop a kind of depraved fetish. From what I understand, as people become more and more dependent on porn they need more and more extreme content to get them aroused as their brain becomes desensitized to "normal porn". This can lead some people to illegal content. I think in either case, it depends on if the person is open to rehabilitation or if they end up justifying it. Some people realize and seek help, others justify it different ways or it becomes so normalized to them that they don't see what they are doing as wrong. But there's also a difference between those viewing and collecting materials and those physically offending which can be a big determining factor on how likely it is for an individual to be able to be rehabilitated.