With some luck, anyone can put together a team of half-decent engineers to build a shiny new product. To build a quality product, however, takes a lot more than assembling a team and making them deliver the MVP in an X number of months.
To achieve greater development speed, some managers tend to deprioritize or discard crucial aspects of software development, such as automated testing and a coherent system design. This enables them to deliver on their promises ahead of schedule, but as time passes by, the entire development process is put into jeopardy by countless surprises in the form of bugs and difficulty to add new features without breaking the existing ones. In their greed to deliver the project as quickly as possible, they end up making the development process slower than ever. What follows next is a loss of trust and confidence in the team's ability. One or two manual QA testers spend hours catching all the bugs as humanly possible, but this reactive measure doesn't address the root cause behind this dumpster fire.
It takes guts to manage the expectations of your clients/business stakeholders and to buy time to build a more robust product. It takes guts not to feel pressured by impatient clients and bring them on the same page as you. It takes guts to set a high engineering standard and maintain it over an extended period.