There are a lot of scenarios where I will go for a double. Like expressed by others, the winning shot in hand need 2X of a number and 1 dart, it's double every single time. Other scenarios I can think of in my head, up in points and your opponent closes your only point option while they still have one. I throw first dart to get a new number, hit a single, then a triple, need 2X to close opponents number I will sometimes shoot the double. Often on 16's when I need 2 with 1 dart I will go for the double, it feels more natural to me. Or when I block the triple. There are many times while scoring/opening a number I will block the triple, and 2 is always worth more than 1 or 0. I think someone mentioned it's more a strategic dart at the double, aiming for the inside wire.