When it comes to using a consumer-grade single-board microcontroller in an industrial environment, some say "So what if it breaks, I'll just replace it with another inexpensive microcontroller." While that may be an option, adding to your maintenance costs is never a winning scenario.
It's believed that up to 20% of plant operating expense is maintenance related. That's a good chunk and planning ahead to add to that percentage isn't a good idea. Besides the cost of replacement parts and the labor needed, you'll also have to consider the possibility of pulling valuable resources away from other projects, the increased probability of a failure during peak production hours, having to keep a large inventory of replacement parts on hand, and if any domino affect will occur from the failure - meaning how will the machine/system react and will other components fail as a result?
When you look at the big picture, it's apparent that the "I'll just swap it when it breaks" method can turn out to be quite costly. And although a consumer-grade microcontroller's initial cost is very attractive, the savings in maintenance and downtime that you get with an industrial microcontroller blows the initial $30-or-so price difference out of the water!