Because a C# GUI on Linux or Mac is not very native looking. Also for the same reason some like Go over Java, static binaries instead of requiring JVM or CLR be

Because a C# GUI on Linux or Mac is not very native looking. Also for the same reason some like Go over Java, static binaries instead of requiring JVM or CLR be installed. On another note, because writing programs in Go is much faster than say C++ or C for most use cases.