The OODA loop in two seconds
Observe, Orient, Decide, Act. John Boyd developed it for fighter pilots in the 1970s. It also happens to be exactly what a puzzle game forces you into, twenty times a minute. A good puzzle game keeps the loop tight: clear visual state, clear action verbs, immediate feedback, new state in under a second.
Why difficulty isn't the goal
Most modern puzzle games are easier than the classic arcade titles. Difficulty was a coin-extraction mechanism in 1980. Today the goal is flow — Mihaly Csikszentmihalyi's name for the state where challenge tracks skill closely enough that attention narrows and time disappears. Tetris hit it. Threes! hit it. Signal//Lock aims for it by escalating the radar's sweep speed and signal density per stage instead of dropping cheap insta-fails on the player.
Mobile killed and saved the genre
Smartphone touchscreens were perfect for puzzles — direct manipulation, short sessions, low system requirements. Candy Crush (2012) put a puzzle game on a billion phones. But it also taught designers to monetise by friction, which made the genre feel sour for a decade. Browser HTML5 puzzle games are the corrective: free, no install, no nag screens, a clean loop.
Why radar fits the puzzle shape
Radar gives you a state (signals on a sweep), a verb (lock), an outcome (cleared or lost), and a new state (the next sweep) within one second. The whole OODA loop fits in a single radar rotation. That's why radar games slide so naturally into the puzzle genre even though their ancestors were action games.