In this episode, we break down one of MQTT’s most misunderstood features — Quality of Service, or QoS. We explain what each level (0, 1, and 2) really means in plain language, how they affect message delivery, and why choosing the right one can make or break your industrial data flow. You’ll hear how QoS plays out in real scenarios — from high-speed sensor updates to critical production alerts — and what trade-offs come with reliability versus performance. It’s a simple, clear explanation for anyone working with MQTT in IIoT environments who wants to finally understand how these settings actually work. For more straightforward insights and hands-on lessons, visit iiotblog.com.