I'll take a shot at this and try to reason and figure it out, if you think my conclusions or reasoning stray to far, feel free to point it out. The first thing

I'll take a shot at this and try to reason and figure it out, if you think my conclusions or reasoning stray to far, feel free to point it out. The first thing I'll do though is replace the term black-hat with non-ethical hacker to avoid confusion and keep the comparison balanced, as there are black-hat conventions and that muddies the terms. Then it seems it is different specializations and how long you can practice your trade. For example, ethical means you are willing to stay within defined lines to accomplish the goal. By being ethical you will often ask for permission before you do something in many domains/fields. Depending on how narrow the restrictions and parameters, you might have to be really creative or attentive to overcome things to accomplish your goals. This applies mainly to website hacking and such, but with permission you could do some of the same things a non-ethical hacker could do as described below. For software and hardware the skill set has a lot of overlap. You would concern yourself in learning or even developing and creating many defense measures since as when possible you would try to come up with a mitigation or fix for any issues you find in any domain. For a non-ethical hacker, you wouldn't ask permission to use subterfuge or social engineering. You would have no problem ddosing a place for extortion, or leaving usb thumb drives in parking lots with malware on them hoping somebody would pick them up and put them in their computer. So your skills in those areas would be higher. You would probably be just as good at software and hardware skills to find bugs, but your purpose and usage would be selling them on the black market and using what you find for ransoming. You would focus on obfuscation and attacking domains. Your motivations being different will lead you to different places. As far as long term, the ethical hacker will remain out of jail, while the non-ethical hacker as time goes on will have the probability they will be targeted by one or more governments and captured increase as time goes on. So due to selection factors some non-ethical hackers might end up with higher skill levels than their ethical counterparts, but many will be caught and lose their temporary advantage, and have their skills atrophy in prison, if they were to go long enough without getting caught to develop those skills. The ethical hacker will be able to use their knowledge as long they are interested in the field and can keep up.