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አማርኛ An exchange matches customers against each other: one backs an outcome, another lays it, and the platform takes a small commission on net winnings instead of building margin into prices. Odds are set by supply and demand, which is why exchange prices are the benchmark sharp bettors compare bookmakers against.
The catch is liquidity: an exchange price only exists in the size other customers are willing to match. Big football markets are deep; obscure leagues and exotic markets can be deserts where the theoretical better price cannot actually be taken.
A bookmaker quotes 2.00 on a team the exchange trades at 2.10. After 2% commission, the exchange back returns 2.10 − (1.10 × 0.02) ≈ 2.078 — still better than 2.00. That gap, sampled honestly over time, is roughly what the bookmaker's margin costs you.