When working through the early stages of a product design, it's common that labels for objects and actions emerge organically. No one is overly concerned about making these labels consistent (yet). But if this proliferation of terms doesn't get reined in early, both product design and strategy get harder.
Do we call it a library, a folder, a collection, a workspace, a section, a category, a topic? How about a document, page, file, entry, article, worksheet? And.. what's the difference? While these kinds of decisions might not be front and center when working out designs for a product or feature, they can impact a lot.
For starters, having clear definitions for concepts helps keep teams on the same page. When engineering works on implementing a new object type, they're aligned with what design is thinking, which is what the sales team is pitching potential customers on. Bringing a product to life is hard enough, why complicate things by using different terms for similar things or vice versa?
Inconsistent terms are obviously also a comprehension issue for the people using our products. "Here's it's called a Document, there it's called an Article. Are those the same?" Additionally, undefined terms often lead to miscellaneous bins in our user interfaces. "What's inside Explore?" When the definition of objects and actions isn't clear, what choice do we have but to drop them into vague sounding containers like Discover?
The more a product gets developed (especially by bigger teams) the more things can diverge because people's mental model of what terms mean can vary a lot. So it's really useful to proactively put together a list of the objects and actions that make up an application and draft some simple one-liner definitions for each. These lists almost always kick off useful high-level discussions within teams on what we're building and for who. Being forced to define things requires you to think them through: what is this feature doing and why?
And of course, consistent labels also ease comprehension for users. Once people learn what something means, they'll be able to apply that knowledge elsewhere -instead of having to contend with mystery meat navigation.