Second, you seem to have a strange definition of "success". Limbo was a success? Well, some people used it, and some software got written in it, and some people used the software. Not much software and not many people, though, in the grand scheme of things. Same with Oberon-2. Even if you consider those two languages to have been successes, Go is a far greater success - it's successful in a way that neither Limbo nor Oberon-2 ever were.