Missing explanation or self misconfiguration?

Type of issue: (feature suggestion, bug?)

Typo

Chapter:

4 / Webpack / Last checkpoint

In the last checkpoint documentation says:

Kill the previous processes in your terminals with Ctrl+C, then run yarn prod:build, and then yarn prod:start. Open http://localhost:8000/ and you should still see "Hello Webpack!".

I'm not quite sure but if we run first yarn prod:build before yarn prod:start will not this change our page as we did before? If we first yarn prod:start and try that does not change as intended and explained.

Am I missing something? PS: I'm a learner it is probable that I messed up somewhere.