Becoming the best hacker in the world is a lot of work, plus it requires quite a bit of resources. These things can be noticed with ease, you can only reroute yourself through so many networks before what you are doing breaks down. This is also closer to being a programmer, you can't just jump into a computer and hack away like they do on tv. Finally, the best work for hackers is trying to find flaws in systems and then fix those systems. People hire you to hack into their own systems to find flaws in their security… that is what most good hackers tend to do.
That's the dfinition of a hacker – being able to hack stuff.
As for legality – depends on what you do exactly and who you work for. Hacking into a phone network while working for the russian mafia would be considered highly illegal, doing the same while in the employment of the company that network belongs to may be your job.
You cant become the best in the world. Most hacking is illegal, yes.
Sure, but you'd have to go to work for the Russians because according to liberal media and Obama they are the only ones who can hack everything! That means they must be the best, right?
You'd be a prime candidate for a long prison sentence, I guarantee, because hacking is illegal!
The first answer is NO. If you got anywhere near the level proficiency you are talking about you would be incarcerated before you got half way there.
The second answer is Yes, probably.
plus very antisocial you could cause someone else a lot of expense and in the worst case senarios cause someone to die if you disrupted systems that peoples lives depend on
Yes and no.