Hardly irrelevant as if that's the strategy, you're going to be left with few businesses to start or invest in. From a practical point of view even a single off

Hardly irrelevant as if that's the strategy, you're going to be left with few businesses to start or invest in. From a practical point of view even a single office site may be such a single point of failure. There are many practical single or narrow points of failure a bootstrapped startup or small business may encounter. The real risk to most starting out business is being seen as irrelevant - by the potential customers or search, whether app store or Google.