The text in a composition is usually all the same length. Every title fits one line, every summary runs to two, every button label is one short word. In that state any layout looks like it works. The problem is that this uniformity does not exist on the real site.
What uniform length hides
Drop real content in and three things surface at once.
First, irregular height. When card titles swing between one and three lines, the button at the bottom of each card sits at a different height in every row. That never shows up in a filler composition.
Second, overflow. A button sized around “Save” meets “Save all changes” and either grows, clips the text, or shoves its neighbour aside. Which of the three happens was not decided in the design, so it gets decided in the build.
Third, underflow — the opposite case, and just as common. A card built for a three-line summary receives a one-line one, and the space underneath reads as an accident rather than an intention.
What to go and fetch
You do not need all the real content. Both extremes and the middle is enough.
On a brand-new site with no content yet, use the closest existing material: sentences from the company brochure, product names from an old catalogue, an email the client actually wrote. It always beats invented copy, because invented copy is invented at the length you wanted.
Two languages behave differently in the same box
Building a multilingual site adds a layer. The same sentence differs in length between languages, and the line-breaking rules differ too. Some scripts break between words; others have no spaces at all and are treated as one unbroken run unless you tell the browser where breaking is allowed.
So a multilingual design is safer when the same screen is built once per language. That matters most for fixed-width furniture: buttons, tabs and navigation.
How real content shapes layout is covered further in the development workflow archive, and the procedure for finding these problems on already-released screens is set out on our process page.
Next part
Once real content is in the design, the next question follows: who is allowed to change it? The next part is about deciding the editable regions up front.