Deciding whether a fee is reasonable requires a comparison against the alternative. Football's transfer market makes that comparison unusually difficult to construct.
Value is always relative to a substitute
A price only means something against what else the money could buy. In other markets that comparison is straightforward because near-identical goods trade regularly.
Football players are not interchangeable, and the closest available alternative may differ in age, position, contract status and league. Every difference weakens the comparison.
The question a club actually faces is what the best available alternative would cost and deliver, and both halves are uncertain.
Availability is the binding constraint
Most players are not for sale at any price, because their clubs have no need to sell. The tradeable population in any window is a small and unrepresentative slice.
A club needing a specific profile may find two or three genuine options rather than a market of them. Scarcity then dominates the price.
This is why fees rise sharply for positions where few players are available, independently of how those players perform.
Internal alternatives are usually undervalued
The relevant comparison often includes promoting an academy player or moving an existing squad member. Those options cost no fee and carry known character and fitness information.
They are systematically discounted because their weaknesses are visible daily while an external target's weaknesses are filtered through highlight footage and scouting summaries.
Familiarity makes the internal option look worse than the data supports, which inflates the apparent case for buying.
Timing changes the choice set
The alternatives available in one window differ from those available months later, so a decision cannot be deferred without changing the comparison entirely.
Waiting may produce a better option or none at all, and there is no reliable way to distinguish those outcomes in advance.
Clubs consequently overpay in a closing window rather than accept the risk of an empty position for half a season.
The counterfactual is never observed
Once a signing is made, the alternative disappears from view and cannot be evaluated. A poor signing might still have been better than everything else obtainable.
Recruitment reviews therefore compare outcomes against expectations rather than against alternatives, which is a much weaker test.
Clubs that document the shortlist and the reasoning at the time of the decision retain the only usable record of what was actually being chosen between.