"The fear of getting it wrong was surpassed only by the fear of not delivering anything at all"

I overheard this comment on a train back into London a couple of evenings ago. Two young trainee lawyers were discussing their careers to date and comparing their workloads - and the high expectations that had been heaped upon their shoulders.

I tried to imagine the circumstances under which somebody in IT would find it credible to articulate a comparable fear. I'm not talking about the natural desire to do things right and to ensure one's deliverables are good quality. Rather, how often do we find ourselves in situations where our professional credibility, the wellbeing of our client (and our own chances of advancement) rest entirely on a single piece of work?

It's easy to think of examples in the "traditional" professions: if you put your name to a company's audited accounts, you'd better be sure they're correct. If you're playing with billions of dollars of your bank's own capital, you'd better be sure your trading strategy is sound. It's easy enough to think of examples from the worlds of medicine and law.

I'm interested in hearing my readers' thoughts on what the equivalents in IT are. I have a few ideas of my own but I was surprised at how few good ones I could think of. I'm hoping you can help me out. So, comments are open as always. I'm looking for examples from your IT career where the outcome of a single piece of work could have had truly serious effects had you got it wrong. "The patient either died or lived". "The defendent either went to prison for life or walked free". "The bank either went bust or made a fortune".... what do you think is the equivalent for a professional in IT?