The main happy paths should work largely fine. If something goes seriously wrong for a large-scale public-facing web site, one of a number of things absolutely must happen:
- Ideally, the company will already know because they will get an error message emailed/displayed on a big screen/whatever
- If it is more subtle, maybe a user will contact the company and if this happens, it is embarrassing, so you act immediately, especially when the bug relates to a happy path that you ABSOLUTELY should have tested
- If it is something with a non-obvious workaround (or none at all) the Development Team make it number 1 priority and work flat out, 24/7 if required, until it is fixed. Why? Because it was a screw up that something so serious got out the door and it is a matter of quality and corporate pride that it gets fixed and quickly.
- The Test Manager gets a serious talking to along the lines of, if this happens again, you're fired.
- The Technical Team has a serious review about how this was allowed to happen and puts in place real measures to prevent a repeat the next time. This is fed back to the Management Team so that people can be accountable where they need to be - the Management Team need to ensure they are getting the whole truth, not just what someone might say to cover their own back.
What isn't OK is:
- Not putting any kind of banner on the web site to say that you are experiencing problems
- Not working with whoever found the problem to quickly work out exactly what has happened and why
- Telling users to delete their cookies to make it work
- Telling users that only some users are having the problem (as if that makes it better that it's broken for me)
- Not properly testing updates to consider not just the new site in a clean happy place, but what happens when a user with existing cookies and a number of different browsers comes back to a new site.
- Acting like a serious bug report from an end user is just business-as-usual rather than, "I'm really sorry, I'm just going to call the Software Manager to tell them" or even, "We know of a problem and the Team are still trying to find exactly what causes it".