Modern day wars are increasingly ending in unwinnable quagmires. It is forcing more and more warring entities to begrudgingly contemplate face to face talks with their enemies.
These drones are being pushed by their sellers as a solution for quagmires: a tool to finish off enemies without suffering huge casualties. As such, drones are emboldening more and more military commanders in chief to put off talks, as they think their new toys are the tool for a cost effective victory (N.B they aren't).