I studied online pedophile communities as it was tangentially related to something larger I was working on in grad school.
So...what I can tell you...is that you can divide them into two distinct groups, initially: Those who act on, are ok with others acting on, and who would act on their compulsions; and those who wouldn't.
Then you get into the myriad other sub-categories that exist within this community.
In general, most of the people in both of these camps, would probably say it's something they can't help. Some might have a reason, others might not. But the overwhelming majority don't present it as some sort of "choice," even if the reason was something like an attraction to the taboo, or a slow desensitization to normal porn.
When it comes to those attracted to underage but post pubescent individuals...that's complicated and I don't feel qualified to go into what differentiates that from other sexual preferences / why the age of consent is morally right but realistically an arbitrary ruling (as indicated by the fact that there is no "standard" age of consent). I guess this is the "jailbait" category and don't act like society doesn't have a double standard on this (not advocating for this sort of thing just saying...this is clearly a different category when it comes to analysis and pedophiles of this brand distinguish themselves as hebephiles so as to differentiate themselves - as a self identified pedophile does in this very thread) Anyway. Physically? I highly doubt many people in this thread could superficially tell who is and who isn't 18 or whatever the law is in your state or country, and this is...I suppose...the defense these people hide behind, superficially. Intellectually? If you are an adult, attracted to what emotionally amounts to a child, even if they are say 20...power dynamics wise...something is up. If that's your desired relationship with a partner. Which get's into the auto-erotic nature of the whole shebang.
With regard to the people who: Are attracted to adolescents, and younger...much younger even...there is something (and again I'm not qualified) fairly cut and dry about it. This is demonstrative of some much larger issues that probably go beyond a simple sexual attraction. Anyway.
So now we start to get into a larger umbrella category - those who don't want to feel this way, and those that don't really care. And once more the whole "would touch a kid" and "wouldn't touch a kid" comes into play because you can have people who don't want to feel this way and would, those who don't want to and wouldn't and so on and so forth.
And then you have the people who want to you know, rape and murder kids. And I think that uh...definitely makes you a completely different brand of monster.
SO my point is...writ large it doesn't seem like a thing anyone chose, just something they discovered. It seems like acting on it, and what one unfortunately does while acting on it, are also subject to whatever else is wrong with that person mentally. But, considering then number of people who a) don't want to feel this way, and b) would never act on it...I think we can safely say that like any other disorder or whatever, you have highly aware and highly functioning people and then their less in control, less highly functioning counterparts. With regard to treatment...I'm of the opinion that that former group could be helped and we should create an environment where they can get that help. However...as a victim of sexual abuse myself...I do have my moments where I'm like "eh hang them all." But I don't think that's how you solve a problem. My own experience is not what led me to this research, but I do think it was part of why I was able to keep my lunch down doing it. I dunno if you have more specific questions I can try to answer them. It's not something that comes up very often so, happy to try and help someone else's understanding with what I know.