That reason being the incredibly popular FDR dying in office after winning a fourth term as president. Before 1945, the only thing preventing someone from running more than twice was the George Washington precedent, and it’s not like FDR was the only person ever to make a go of it.
The two-term limit has honestly always struck me as kind of odd. I get that George Washington stepped aside in part to ensure that the system outlived him, but we’re 240 years removed from the need to teach the nation to expect and embrace routine, peaceful transitions of power (I hope…). If it’s supposed to be a bulwark against tyranny, the fact that this country lasted over 150 years without it sort of belies its necessity. If it’s supposed to be a check on the risk of a president dying in office, the degree of scrutiny placed on modern candidates’ medical histories makes the amendment somewhat redundant. I just don’t see how preventing a person from seeking a third term is inherently any better or worse than letting the same party win more than twice in a row - something which has also only happened once since the 22nd amendment was ratified (Reagan, Reagan, Bush I). If the president is popular, and Americans are willing to support them, I don’t see the issue. We can always vote them out in 4 years. If anything, the term limit seems like it removes accountability; the president can essentially do whatever they want for the last 2 years of their second term, because there’s no way to hold them to task for their actions at the ballot box.
Long-term, I don’t think America has a dynasty problem, nor do I think it really has much of an appetite for them. The Clintons would be only the 4th family to ever hold the presidency multiple times (the others being Adams, Roosevelt [kinda], and Bush). The quirks of our current political class and informal party nominee succession practices have meant that the people in charge have largely been the same for the last 20-ish years, but I don’t think that’s sustainable for more than one or two more elections. Looking ahead to 2020 (for the Republicans) and 2024 (for both parties), I don’t really see anyone who would be willing or able to take up a dynastic banner. Hillary’s daughter seems unlikely to run, and the Bush dynasty - such as it is in national politics - seems to have been effectively run into the ground by Jeb and W. Short of Michelle Obama making a return to national politics in 2024 against all expectations to the contrary, I think the next non-incumbent election and beyond are going to be between two names with no presidential history. They’ll almost certainly be people who have been around for a while, because for the most part you don’t get to come from total obscurity and run for president, but it’s not like we have nothing but a pair of ruling houses to look forward to.
