To check our Wi-Fi signal reception, we tend to look at the signal notification icon of our devices: the more bars, the better the signal. But more often than not, the amount of bars doesn’t give us a good indication of the quality of our connection. We've all had situations where 4 or more bars are lighting up, but websites are still loading agonizingly slow. To make things worse, a lot of professional Wi-Fi planning and comparison tools use this same signal strength metric as a substitute for Wi-Fi throughput! This blog post will show that the Received Signal Strength Indication or RSSI of a link (which is basically a numeric value for the number of bars) doesn't correlate well with the throughput that can be achieved on that link. In other words, big investment decisions in Wi-Fi infrastructure turn out to be based on paltry data at best.