I will suggest that you fail when you give up and no company is ever completely free of the threat of failing, no matter how long they have been around. If you

I will suggest that you fail when you give up and no company is ever completely free of the threat of failing, no matter how long they have been around. If you hit challenges that the C level staff cannot overcome, then you are likely to die. But C level staff are often able to do "the impossible." It is going to be nigh impossible to determine that something is certain to fail. Paul Graham suggests that startups need to just "not die" to eventually make it. I will suggest that this continues to be true, even after they are worth billions of dollars.