The Milky Way Galaxy, our galaxy, which we are all a part of is going bye bye as it is now past middle age and closer to galactic death. The Milky Way immediately stopped birthing stars about eight billion years ago after forming a thick disk shaped like a saucer. This means that “quenching” can happen even before galaxies run out of gas.
Once believed to be driven mostly by the amount of gas a galaxy has to build new stars with, it is now not clear whether life cycles of galaxies are determined by losses of their raw material abruptly when it is ejected by supernovae or a central black hole, burning through their reserves slowly, or ceasing growth for a reason(s) unbeknownst to man.
There is believed to be a connection between the thick disk formation and what is called the “quenching” of the Milky Way. The disk and bar structures may be disruptive to growth by stirring up the gas, making heat so hot that it hinders star formation. Other evolving spiral galaxies may even be aging in a similar fashion.