Answered with numbers you can check — including ours.
Over/under goals markets suit a Poisson-style model better than the match result does, because the model produces a distribution of total goals directly. There is no need to convert into a three-way result, which is where a lot of information is lost.
The main drivers are each team's scoring and conceding rates, the league's baseline goal rate, and match context such as a cup tie with a rotated side or a team needing a result. League baselines vary widely, and using one global expectation across all of them is the most frequent modelling mistake.
Over 1.5 and over 2.5 sit at very different prices and demand very different strike rates. Over 1.5 often trades near 1.20-1.35, which needs roughly 74-83% just to break even - so a high strike rate there can still be a losing market.
That is not hypothetical. In the MalluSports published record, Over 2.5 Goals is currently the model's worst published market at -29.2% ROI over 15 settled picks. It is shown next to the profitable markets at mallusports.pro/data/ rather than removed, because a per-market breakdown is the only way to see where a model actually works.
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