Personal-computer and account security rarely comes down to one dramatic exploit — it comes down to boring, consistent policy enforcement at the login gate. This 2D diagram lays that policy out as a lane: simulated credential-guess attempts stream from an attacker marker toward an authentication gate at a rate you control, and an exponential-backoff rate limiter decides, attempt by attempt, whether to even evaluate them. Each failure widens the delay before the next attempt is allowed exponentially, visualized as a closing red barrier at the gate, while a scrubbable history chart plots the backoff delay itself climbing and resetting over time on a log scale, and a live histogram tallies how many attempts were blocked outright versus actually evaluated. Tune the attacker's rate and the credential's entropy against the defender's base delay, lockout threshold and idle-reset window to see how quickly — or slowly — a sustained brute-force attempt gets throttled to a standstill.