Regarding the 'buy vs build' I think buying software is one of the most risky things that you can do. Since it cost money you cannot then say 'o well, i guess it just did not pan out, let us just not use it'. Now you are kind of married to the software. And some of the worst software out there is paid for. E.g., jira vs. redmine. This is actually a bit ironic considering the fact that I actually am writing software in my job that is sold.... O well, it actually is sold as a part of a piece of hardware, so it is not really sofware as such.....
Regarding the last point, failure can be made uncommon if a relatively safe route to production is available, starting with a language that verifies the correct use of types, automated tests that verify the correctness of code, a testing environment that one attempts to keep close to what production is like and so on. Getting a call that production is not working is the event that I am trying to prevent by all means possible, and I think research would be able to show that people who get fewer calls, not just because production is failing, but in general, fewer calls regarding whatever subject, will live longer and happier.