More experienced software engineers can usually make the right design decisions that don't mean rebuilding when/if it comes time to scale things. This is usually about avoiding bad decisions because they know better.
In the abstract, it's impossible to judge decisions. What's worse than a company that spending millions on refactoring? Not being able to spend money on that because the company went out of business before launch because the devs were too busy engineering the most perfect, webscale architecture for the system that they weren't able to launch a product before running out of runway.