@gunrunnerjohn posted:No offense, but the consequences of a screwup in development in the toll industry is a traffic jam. The consequences of a screwup in my working career in avionics developing flight critical electronics is being featured in a headline about an airplane crash where a couple hundred people died!
John, I'm not offended, but you are being a bit selective in your response. I also mentioned electric cars. Some of those are self-driving. A screw-up there could cost lives. And from the 1980's to present day, software screw-ups have occurred in various life-ending or financially painful scenarios from X-ray machines to FB-111 to Arianne rockets to Patriot missile batteries.
But since you selected "toll industry for $100", I'll inform you that the least significant consequence of a screw-up is a traffic jam. A software screw-up is much more likely to cause one or more of the following to occur:
- Thousands (or millions) of customers are improperly charged for their trips because vehicle classification (identification) is inaccurate or not working
- Fares are incorrectly computed - either ticket or E-ZPass
- Toll violations are attributed to the incorrect vehicles
Here's the impact:
- Thousands (or more) of angry customers flood the toll agency with demands for refunds. That all costs time and money to straighten out. Sometimes (e.g. WorldCom in New Jersey in 1997-8) that leads to lawsuits and calls from legislative bodies to disband the toll authority.
- Any credibility of the toll system gets shredded, affecting audits of toll takers and labor relations (if the toll collectors are unionized, for example). You can't audit someone robbing the till because you'll lose in court.
- The toll authority gets an incredible amount of publicity - all bad.
- Depending upon the nature of the maintenance or warranty contract, the system provider could be liable for liquidated damages (typically an amount of $ / incident or period of time, e.g. $100 / hour / lane. Toll highways typically have hundreds of lanes - you do the math).
- The toll authority might call the system provider down to a televised meeting and ask "Why are you such a ****-up?"
As my mentor told me years ago: In the toll business, you are successful if no one knows your name. I've been good and fortunate and I'm a ghost - not even a vapor trail. 
But John, you are right: Nothing is so easy as the job you imagine someone else doing! 
George
