Write explicit code, write tests, have QA staff and procedures, build what the stakeholders what.
I guess the biggest problem with software quality is not that we don't know how to do it, but that it's expensive.
Flinging crap out fast is sometimes seen as a valid business model (unfortunately): that crap is only expensive to you if you have to maintain it, but that's not your problem if all you're trying to do is to "exit".
On the other end of the spectrum (like where I work at now for example), we take a lot of effort and time to make sure our code is not crap - but that is an expensive decision both in terms of money and time.