The reason first come first served changes who arrives

Allocating by arrival order is presented as the fair alternative to allocating by price, because nobody is excluded by having less money. Nobody is excluded by money and the good still has a cost. It is paid in hours of waiting, and hours are not equally available to everyone, so the queue performs a selection of its own.

What everyone sees

First come first served is read as the absence of a rationing rule — open access, no criteria. It is a rationing rule with a specific price. The price is denominated in a currency that is invisible on the balance sheet, which is why the mechanism appears neutral while producing a systematically skewed set of recipients.

What is actually happening

Barzel analysed rationing by waiting formally, showing that when price is held below the clearing level the difference is dissipated in queueing costs, and that the resource goes to whoever has the lowest value of time rather than to whoever values the good most. Weitzman compared price and non-price rationing directly and found that which mechanism delivers a good to those who need it most depends on how need and ability to pay are distributed, so neither method is generally superior. Both results describe the same conclusion from different directions: the allocation rule is not a neutral procedure but a specification of what participants must spend to qualify.

Why it stays hidden

The selection hides because the people it excludes are not present to be counted. The queue is visible, the recipients are visible, and those who could not spend a morning waiting are absent from every observation. Their absence is then read as a lack of interest, since the only evidence of demand the system records is the willingness to queue.