unsustainable

adj

1. Not sustainable.

   “You don't have to be Einstein to work out that this level of government subsidy is unsustainable.”

   “RTDs cover a multitude of sips, including: “hard” or “spiked” teas, coffees, kombuchas and seltzers; […]. And although the sector was birthed in the ’30s by drinks like Campari Soda, and boomed in the ’90s with Bacardi Breezer and Smirnoff Ice, RTDs are now at a point of seemingly unsustainable saturation.”

noun

1. Something that cannot be sustained.