The goal of almost any product team is to move as fast as possible and build a quality product. The “cost of quality” cuts two ways: there can be a cost of shipping something that is low quality, and there can be a cost to shipping something that is high quality.
The cost of shipping a low-quality product is degraded user experience (imagine bad reviews, lost customers, etc). But the cost of shipping a high-quality product is a decrease in your team’s speed.
Time is valuable, and spending too much of it polishing features or conducting extensive QA takes time, especially when the Pareto principle comes into play (the last 20% of the work could take 80% of the time). What is the cost of the chance of a few small bugs? What is the cost of starting the next team project a week later, but raising the quality bar of the current workstream?
The cost of quality is yet another area that requires finding balance.