It is an unfortunate weakness that keeps us from simply voting the bum out. We keep our man in office to try to recover our 'fair share' of goodies from the government trough. We get career politicians.
So are term limits the answer? It seems like we need them, because it's clear that an entrenched legislator becomes corrupt. The voters in those other states (it's never 'our guy') just keep re-electing the same ones. How did it get this way?
If we look at the Constitution as ratified at our nation's founding, there is no provision for bacon distribution. Article I Section 8 does not establish a pork system for the use by the legislature to ensure their re-election. That didn't come along until the sixteenth amendment, ratified in 1913. It allowed the federal government to lay taxes without regard to census or enumeration. It allowed the government to skim money from the productivity of its citizens for its own purposes.
The same year, the seventeenth amendment destroyed the Senate, which was intended to equally represent the states and to act as a damper to the more populist House. Now it is elected by the people, not by state legislatures. This makes the Senate more populist. It makes the composition of the Senate subject to more influence by the nation as a whole, especially when the federal government has the ability to collect and distribute money. It is no longer the less volatile, more staid body of the legislature. It is another House (where revenue bills are supposed to originate).
[What else was going on around 1913? Probably nothing relevant to this discussion...]
Two later amendments attempted to rein in some adverse effects of the sixteenth and seventeenth amendments. In 1951, the twenty-second amendment attempted to curb the excess brought about by FDR, who was elected to four terms as president. Roosevelt was a flagrant bacon distributor. It was an attempt to treat the symptoms, and did not go far enough to have a meaningful effect.
Term limits are not the solution. To cure the fundamental problem, the sixteenth and seventeenth amendments should be repealed. There should be no earmarks, pork barrel projects, appropriations or any other vehicles for the legislature to use in order to buy votes. Term limits would be unnecessary, because the mechanism for corruption in the legislature would be dramatically reduced.
However, term limits could be a useful tool to help achieve the repeal of these amendments. If there is less pressure to be re-elected, good senators and representatives will be better able to resist corruption. No one dares try to cut off the bacon supply now, but with nothing to lose, the legislature could repeal laws and amendments to do just that. After the damage caused by the sixteenth and seventeenth amendments is reversed, term limits will become irrelevant.
Can we do this overnight? Nope. It took a hundred years to get this way. It's a physical addiction. We have to have good, honest men with the courage to begin the process. And we have to elect them.