The idea of an incumbent goes back to the creation of governmental systems. Even in ancient Greece and Rome, there were incumbents to political races wherever there was the idea of an "election". Ancient societies aside, the incumbent system has been a staple in the United States since the dawn of our democracy.
If you aren't aware of what an incumbent is, let me educate you. An incumbent, simply put, is the current holder of an office. The way in which an incumbent system works in the United States is simple. Generally, the incumbent in a political race is one who currently holds the office in question. There is no set record for winners or losers, but it is generally accepted that incumbents do better in the races they run.
Of course, there are exceptions to this. If an elected official fails to do a good job and is rejected by the voters, that person stands a good chance of losing. In the United States, we have some term limits which are in place to not allow an incumbent to run repeatedly for the same office. The 22nd Amendment to the United States Constitution set term limits for the President of the United States, barring the office from being held for more than eight years.
The existence of an incumbent limits political freedoms in the United States.
Take for example the 2020 Presidential Elections. There are currently eight candidates seeing the Democratic Nomination for the Presidency in 2020. That is a big number, which continues to grow each day. This provides many diverse platforms and an array of choices for voters. This aspect of choice is a good thing. Regardless of your candidate of choice, you will still have some amount of say in who the Democratic Nominee is.
However, on the Republican side stands Donald Trump. Regardless of your political affiliation or your views of the Donald, he is almost certainly going to be the Republican Nominee for the Presidency in 2020. Donald Trump is an incumbent, meaning that he currently holds the office which he seeks. Although he may not win the 2020 Presidential Election, Donald Trump will be in the running as the nominee.
This is a bad system from which to govern. I do agree that only holding the Presidency for four years may not allow you to accomplish all of which you set out to. But whoever does that? When it comes down to brass tax, it is up to Congress to pass bills which fulfill the Presidents agenda. I am not saying that the incumbent system gives an unfair advantage to the incumbent, although some may make that argument.
I am simply saying that the incumbent system is bad for democracy.
An incumbent system limits the choice of the voter. A government of the people, by the people, and for the people shall not perish from this Earth. Lincoln said that, and he was an incumbent in 1864. But just as this type of government shall not perish, is it really for the people?
Even in a primary election where nominees are selected, voters should still have a choice. I believe it to be the right of all people to demand that there be more choices, even if the incumbent is the favorite. People should have the ability to cast their vote, even if to show that the incumbent isn't as popular as he or she thinks they are.
I cannot say that I have a solution to this problem. Maybe it isn't really a problem at all. Maybe the incumbent system is better for democracy because it allows someone who has power to more easily attain power. Maybe this system allows for political problems to be solved more efficiently. The problem with this thinking is that there are a lot of maybes.
The only clear truth is that the incumbent system limits the power of the voters. Maybe that's a bad thing.