It really comes down to risk management. Engineering is the discipline of making trade-offs, one of which is deciding when a risk is acceptable. If the risk to

It really comes down to risk management. Engineering is the discipline of making trade-offs, one of which is deciding when a risk is acceptable. If the risk to your end users is low, or the hazards are minimal, then yeah you can push crap code to production daily because nobody is actually harmed by it. If the crap code carries a risk of say bringing down your payment or accounts system, causing you to lose revenue, then you might spend more time mitigating the risk by testing, reviewing, and improving the code. On the extreme end of the spectrum, where the hazards posed by bugs crash your spacecraft into the atmosphere or break your $300 million dollar probe, you tend to spend a lot of time validating and verifying your solution because a single mistake is very costly.