Java (programming language): The license agreement of Java says, You can’t use Java to run a nuclear power plant. Why do you think SUN cared to incorporate this point?

According to the license agreement:
"You acknowledge that Software is not designed, licensed or intended for use in the design, construction, operation or maintenance of any nuclear facility."

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This is a clause acknowledging Java, back in the days of Sun, being unsuitable for applications requiring real-time performance.  The key factor is the JVM's garbage collector, which can hinder performance at unpredictable intervals.  This Q&A explains it pretty well, where if Java's garbage collection kicks in just when an application needs to do something to avert a meltdown, it might not be able to.  There's also mention that the Windows EULA specifically addressed the Windows version of Java likewise being unsuitable for other real-time applications.  Sun likely was just trying to avoid the nastiest possible disaster that can happen, keeping accidents at Chernobyl and Three-Mile Island in mind.  I'll conjecture that nuclear power plant has the best chance of any technology to be directly responsible for the accidental death of the greatest number of people due to a software inadequacy.

I'd like to also point out that Oracle, who has since bought Sun, now includes a license agreement with Java that contains no such clause.