The Founding Fathers didn’t expect that serving in Congress would be a lifetime career. And for a century, it mostly wasn’t. The first election in which more than half the incumbent members of the House of Representatives were reelected was in 1898. Since then, a majority of House members have been returned in every election except 1932.

That’s the context in which to weigh the fact that three incumbent Republican House members who have been comfortably reelected have recently announced they are retiring — and the rumors that more will do so. Incumbents tend to know, and be known in, their districts. They usually win, while open-seats contests often result in changes of party control.