The “what would happen if you were hit by a bus?” is always a useful test. It applies to equally well to running a business or project, or to a family. We will all be replaced sometime, whether in a planned way or unexpectedly. Having contingency plans in place makes it easier for you or other people to cope.
A well known example of what can happen is Michael Schumacher. After a hugely successful career in Formula 1, he was left severely disabled after a skiing accident. There must have been a sense that the risk of injury was past.
Less well known is Casper Gray, who set up a business helping SMEs to raise funds, but then developed multiple sclerosis. His condition has deteriorated, and he finds himself in the position of disabled entrepreneur. But determined businessman he remains.
The plans should deal with succession, and with passing on knowledge, contacts and processes. Making the time to do so is often a problem.
Keyman insurance should cover the business as well as the business owner, so that the business has cash to hire a replacement.
The other important issue is making a will, with any necessary tax planning. Ensure that your dependents are looked after.
I hope it never happens to you, but what are your plans for an unfortunate encounter with a bus, whether it looks like a bus or not?