Every load of that screen was the first one
A till gets opened at eight and used until close. A guest’s phone meets your menu once and never comes back to it. Averaging those two together produces a number that describes nobody.
We keep a board of how long every page in the product takes to appear, on real phones and real tills, and anything averaging over 300 ms is treated as a job. Last night one page went over for the first time in days. Before touching it we looked at how the number was made, and the answer settled the whole question.
Six loads recorded. Six of them cold. Not one warm load in the set.
Cold and warm are different questions
A warm load is a screen opening on a device that already has the app: your till at half past two, your kitchen screen after the first ticket. The download happened hours ago. What you are timing is the screen.
A cold load is the first one after the device arrives with nothing: the till at eight in the morning, or — every single time — a guest's phone scanning a code at your counter. What you are timing is mostly the download.
Those are two different complaints with two different fixes, and one average across both answers neither. That is why our board splits them, and why the first thing to read on a slow row is not the average but the split beneath it.
The page with no warm loads at all
The page that went over budget is the one embedded on our own home page so visitors can poke at a live menu. Nobody opens it twice. There is no repeat visit to be fast, so its number is not a screen being slow — it is a download being counted, honestly, every time.
Which makes it a useful thing to have measured, because it is the same page a guest meets. It just does not mean what a slow row usually means.
What to do with this in a venue
When somebody tells you the system is slow, the useful question is which load. "It takes ages when I first open it in the morning" and "it lags when I press a category at seven" are unrelated problems. The first is about what the device has to fetch; the second is about what the screen has to do. Fixing one will not move the other, and a supplier who answers both with the same sentence has not looked.