Think of it this way. You're the owner of a tech business and you hire a person whose resume says he/she has the experience and education with coding that can make your business more money so you hire them. Turns out he was buying code from a website and passing it as his own but then you need him for a special project where he's unable to complete it because he can't get the coding he needs because it doesn't exist and he lied about his knowledge so he can't make the coding. Then you find out he's not the expert you thought he was. He lied to get the job, used fake coding to show off his skills and took your money while not actually working.
Basically, this is what happens when someone tries to cheat YouTube into giving them monetization. The problem becomes that even if you manage to get 1000 subs and 4000 view hours through cheating (wasting money in the process) and manage to get into the YTPP, you still have to get views in order to get paid by YouTube and it will take hundreds of thousands of views to see any worthwhile money and it will cost you more to pay for views than the money you'll make so it will be an even bigger waste of money. And that's if YouTube doesn't catch on, which they will because Youtube has been doing this long enough to know how cheating works. In essence, if you found these videos, YouTube knows about these videos and knows how to find out who's cheating.
It's that simple.