Engineering textbooks are essential. They teach fundamentals, equations, and idealized system behavior. But industrial projects rarely operate under ideal conditions. After more than 15 years of working on live industrial sites, one lesson becomes clear: real engineering is shaped as much by people, processes, and uncertainty as it is by calculations. One of the earliest realizations is that data is almost never perfect. Flow rates fluctuate, compositions vary, and operating conditions drift over time. Textbooks assume defined boundaries; plants operate in grey zones. Experience teaches you to identify which data points truly govern system behavior and which ones can be treated with conservative margins. This judgment cannot be learned from theory alone, it develops only after seeing how small data errors translate into large operational consequences. Another critical learning is that systems are only as good as their operators. Designs that assume ideal operation, perfect maintenance, or constant attention often struggle in practice. Over the years, we learned that successful engineering must account for human behavior, shift changes, workload pressure, and practical maintenance habits. A technically elegant solution that is difficult to understand or maintain will eventually fail, regardless of how good it looks on paper. Long-term project exposure also teaches that simplicity is not a lack of sophistication. Early-career engineers often associate complexity with intelligence. Experience teaches the opposite. The most reliable systems are usually the simplest ones that adequately address the problem. Eliminating unnecessary components, reducing operational steps, and designing for clarity often delivers better performance than adding layers of control or equipment. Another lesson rarely discussed in textbooks is the importance of designing for abnormal conditions. Most failures do not occur during normal operation, they occur during startups, shutdowns, power failures, or process upsets. Over the years, repeated exposure to such events reinforces the need to ask uncomfortable questions early in the design stage: What happens if this stops suddenly? What happens if the load doubles? What happens if the operator responds late? These questions are born from experience, not formulas. Industrial projects also teach that engineering is a long-term responsibility, not a one-time deliverable. Equipment that performs well during commissioning may behave very differently after months or years of operation. Material compatibility, corrosion, fouling, wear, and process creep only reveal themselves with time. Seeing systems evolve in the field builds an appreciation for lifecycle thinking. Designing not just for performance, but for durability and adaptability. Finally, perhaps the most important lesson learned over 15+ years is knowing when to question assumptions and when to say no. Not every specification is correct. Not every request is safe or practical. Experience builds the confidence to challenge inputs, explain risks clearly, and propose alternatives, even when it complicates the conversation. This is where engineering transitions from execution to responsibility. So, Textbooks build engineers, Experience builds judgment. At Apzem, our approach is shaped by both, but guided by what years of industrial reality have taught us: good engineering is not about perfect conditions, but about predictable performance in imperfect ones.
