Earlier quoted context omitted.
Not a bad idea. What if the government offered free tubal ligation and vasectomy. If you later want to have kids that cost is on you to reverse it.
The vasectomy (and I guess the tube ligation as well, I haven't looked into it) is NOT reversible. You can try and there's some success rate, the sooner you do it the better chances, but it's not a reversible method. Don't use it as contraception, it's easier to educate and use different methods.
Once you have decided that you do not under any circumstances want children, the only better way to prevent it is abstinence.
Some people do not ever want kids.