My car already has the few things I need in the trunk. All I need to do is check the weather and choose what clothes to wear. Having a road atlas for the entire United States means I can navigate without a phone. (Which has happened.) Having an extra hoodie and a pair of old boots means I can walk several miles in snow.

All of these items have been used or badly needed the past.

If I was starting a company, I’d do similar things and I wouldn’t worry about failure and would take risks, even serious ones, with confidence.

Mentally preparing for failure is a perfectly reasonable thing to do, but it's not about "feeling sad" and "giving up", but about thinking through all the things that may ruin your business. You'll also be less shocked when you do fail.