Premature optimization may hit them hard. Overengineering is imo usually the bigger technical debt and a huge upfront cost as well. Well-thought out plans tend to become a sunken cost fallacy. Making room for changes is hard enough in XP like ways of working. When you have to tell your manager that half a year of careful plans and engineering can be thrown away, because of the new requirements, which emerge from late entry to market, you look like a clown. Plans and complexity usually introduce more risk than less.