No no, you aren't missing something, it is definitely always better to know what you want. 4s shouldn't be used much outside of bugs and spikes. The critical part here is the word "exactly." Take a bug for example. The ticket would be something like "Fix blank page error" becuase we obviously know the gist of what's going on, but we really don't know much so it's a broad goal of "fix it." So, that would be a 4.

Now, after investigating, maybe it turns out the data was malformed, so there are two options: make a new ticket or just complete the main bug ticket. If you make a new ticket, it would be a 2: "Gracefully handle data when it is malformed." We know exactly what we want to do, but still not how to do it. We usually just solve the bug in the same ticket to keep the board a little cleaner, but if the solution turns out to be multiple steps, then we would make new 1 and 2 tickets.

The other example is a spike ticket, which is researched based. Those are usually questions like "Can we set up a DataDog monitor on our legacy project?" Which are by definition vague as well. In fact, while researching the spike, we might find out that DataDog can't work, but turns out NewRelic will. So a new ticket is created after the spike: "Setup new Relic with legacy project," which would be a 2. Becuase we know exactly what we want, but again, not how to do it. (if we did know how to do it, then it would be a 1).

4's are not super common, in fact they're pretty much only for Spikes, Bugs, or vague client requests that are on a deadline. You should not have a lot of 4s on your board, in fibonacci a parallel would be that you have a bunch of 13s; clearly things are not being maintained and communicated well enough.