--- date: "2026-07-22" mat: "2026-07-22T11:22:16Z" title: Red Or Green --- # Red/Green vs Green/Red Many years ago, I was writing the documentation[^techwr] for version 2 of an order management system[^escom2]. It was unusual for two reasons. Firstly, it was a genuine X-Windows / Motif application. So, although everybody has a Windows desktop, they had to fire up an X-Windows app and connect to this application that was running on a DEC VAX, which itself talked to another DEC VAX running the backend OMS that was running VAX-COBOL. Yes kids, this is how the world worked in the late 1990s when you're a massive global enterprise. Don't worry, they eventually migrated to SAP ERP, so that was an "improvement"[^migration]. Secondly, the UI has the weirdest color scheme for action buttons, and I never could get my head around it. On the Windows side, green for go, red for dangerous stuff was the UI norm. But the OMS running has deliberately configured the Motif widgets to use red for OK and green for the dangerous stuff. It drove everybody crazy, and nobody wanted to explain why (not even the product manager), because either it was too embarrassing, or even more embarrassingly they did not know and didn't want to admit it. Many decades later, I finally get what the logic was: whoever designed it was thinking like an electrical engineer and not a software engineer. Obvious, eh? Let's dive into the fascinating world of traffic lights[^rag]: - red = stop / danger / oops - amber = caution / warning - green = go / safe / proceed Most people, through day-to-day life, are intimately and subconsciously familiar with the traffic light model, so when Xerox started to work on HCI and develop GUIs they simply adopted what was familiar. In industrial electrical engineering, which predates software engineering, they use a different scheme: - red = live / energized / connected => don't touch or zappy-zapp! - amber = attention / caution => something is happening - green = de-energized / open no voltage => safe to touch/maintain And I only learnt about this because I recently found and started to watch [Cursed Controls](https://www.youtube.com/@Cursed_Controls/videos). So, whoever designed that OMS was thinking like an electrical engineer completely oblivious to the fact that the software field did things differently. That nobody questioned this when they built out that software was an interesting reflection on the cultural[^culture] and organizational dynamics[^politics] at play. [^techwr]: You think those 500 page manuals appeared by magic? In this case, it was unusually formatted: A5 landscape, two columns, and presented using an Information Mapping like structure and sublimne typography so it didn't suck. It combined text and visual flows to make using this less than easy to use application as usable as possible (although we all know that nobody ever reads the manual, and you wonder why technical writers have a tendancy to go postal?). [^escom2]: Enterprise Supply Chain & Order Management (ESCOM2). [^migration]: The migration from a proprietary in-house fully-customized COBOL system to SAP ERP went about as well as you can expect. [^rag]: or railway signaling, which uses the same colors, came first, so when traffic lights they used what was familiar because that makes things easier. [^culture]: Italian management vs French hierarchy. On the positive side, while the office was a madhouse of politics, being based in France the company restaurant was gourmand's delight (and the lunchtime glass of wine greatly helped). [^politics]: The internal politics were so typical for the cultural background of the management team it was like working in a hyper-realistic cliché. One example was a complete refusal by one of the middle-managers to proof the documentation because "it is too much to read". The solution: print it doubled-sided and he was as happy as a pig in shit to review it because "Bene. Less to read now!". Life is never simple, and the next week the department manager had a fit because somebody (that would be me) had done too many things with the photocopier and their monthly department usage count had trended upwards instead of downwards. The irony being this was the same manager who insisted I gave copies of the documentation to all the middle-managers to review, and as one in particular refused to accept a ream of paper to read, and the local printer was simplex only, the only solution was to (ab)use the corporate duplex photocopier. The Dilbert cartoon was perilously close to real-life.