Buying the first Particle Accelerator and watching its cost jump from 1.00 to 1.32 made the loop clear right away, and the Guide tab listing what unlocks at 1.00 b atoms, then Lives, Humans and Super Humans, gave me a real long-term target. The start felt slow though: at 0.20 atoms/s I sat looking at greyed-out Buy buttons for a while. A click-to-make-atoms button or a cheaper second generator would keep the first minute active.