Why markets vanish close to kick-off

Thin markets are pulled when the book can no longer price them safely, most often because a piece of information is pending.

A market's price depends on assumptions. When an assumption becomes unresolved — a lineup delayed, an injury unconfirmed — the price cannot be maintained and the only safe action is to remove it.

Markets also close simply because the event is starting, which is a scheduling matter rather than a signal.

That is also the expensive part. A market being unavailable is a stronger statement about uncertainty than any price the book could have posted, and it is a statement most readers never notice.

What to do with it. When props disappear before a game, treat it as news that something about the lineup is unresolved.