They do a pretty good job of using your tax dollars to "buy votes" and get re-elected.
Government programs are not designed to create wealth/income, so you can't use that to determine whether or not a government program is successful.
At the most, welfare programs should only be designed to get you through a tough situation so you can get back on your feet. Instead, they only seem to create more and more dependence (that is the bureaucrats measure of success and the more money they can spend to do it, the better). The dependency class is going to vote for the people giving them free stuff every time.
On the other hand we have government agencies like the FAA, which help keep our airports running smoothly and prevent planes from running into each other. That's a good thing. Of course, they have to do it with equipment that was obsolete 20 years ago.
The answer as to why Congress and bureaucrats can’t get things done right is that they are UNACCOUNTABLE! Lazy Americans do not hold them to campaign promises and to their duties and responsibilities under the Constitution. When we wake up and make them accountable or throw them out of office, they may get the message...but the people have to take responsibility too...sadly, I don’t see that happening!