Usually feels like
Seconds
It finishes while you are still looking at the screen.
It is seconds because the image is tiny, and because the page it belongs to has already arrived by the time you notice the gap.
The wait, in plain words
You are looking at a sign in form with an empty rectangle in it. The boxes are there, the button is there, the picture is not. Nothing is broken yet.
The picture is a separate thing from the page. The page is markup and came as one piece. The image is made on demand for your visit, and it travels its own journey along the same path a moment later. It is behind the page because it was sent behind the page.
Markets of this shape keep the image small deliberately, which is why the gap is short. It is also why a rectangle that is still empty after the rest of the screen has settled deserves a different reading.
Underneath, while nothing moves
Two things have to happen before the rectangle fills. The market has to generate the challenge, which means making an image tied to your session and to nobody else's, and that image has to make the trip. Both are quick. Neither is free.
The order is fixed by how a browser works. It reads the markup, finds a reference to an image, and only then asks for it. That request cannot begin before the markup has arrived, so the picture is structurally later than the boxes. There is no arrangement in which it comes first, and none in which it beats the first screen painting.
The consequence people miss is that the challenge is bound to the session that fetched it. Reloading the whole page does not merely fetch the picture again. It discards the challenge, asks for a new one, and empties anything you had already typed into the form above it.
That makes a full page reload the most expensive available response to a slow image, and the one most often reached for. If the image alone is missing, the image alone is what is worth another attempt.
Behaving, and not behaving
There is a clean split here, and the browser draws it for you if you look at the rectangle rather than at the clock.
An image that is on its way
The space where the picture goes is blank, or holds a plain frame, while the rest of the form is drawn and usable. The tab still shows activity.
It fills in one step. Small images do not fade in over this network, they simply appear.
An image that is not coming
The space holds the browser icon for an image that failed. That icon comes from the browser, and it means the request for the picture ended rather than stalled.
A failed image is a different problem from a slow one. The request completed and produced nothing usable, which points at the path or at the market rather than at the wait.
A blank rectangle and a broken image icon look similar at a glance and mean opposite things. One is a request in flight. The other is a request that has finished badly.
If the icon appears, asking for the image again is reasonable. If it appears again after that, the picture is no longer the problem and the wait has left this band.
Safe to do meanwhile
The right moves here are small and local. The wrong one is large and global.
- Reload the image on its ownMost browsers offer this on the image itself, and it leaves the form and its contents intact.
- Type the rest of the form firstNothing stops you filling the fields above while the rectangle is still empty.
- Look for a refresh control beside the challengeScreens of this shape usually carry one, and it is the intended way to ask for another.
- Read about failing it repeatedlyA picture that never arrives and a picture you keep getting wrong are different problems.
- Leave it a moment longerA small image on a long path is often just behind, not lost.
What makes it longer
The image is small, so nearly everything that lengthens this wait is about the trip rather than the picture.
- A path already carrying the rest of the page, so the picture queues behind it.
- A market generating challenges under load, which delays the making before the sending.
- A gate screen in front of the sign in screen, which means two challenges in a session rather than one. See the gate screen holding you.
- Reloading the page, which restarts the whole arrival rather than the part that was late.
- A browser set to block images, which turns a wait into a permanent absence.
- Asking for a new challenge immediately after a failed attempt, which some screens answer with a harder one.
What this card is not. This card is not about reading a challenge you cannot solve, only about one that has not arrived yet.