Why three 60% picks don’t make a 60% combo
Why you multiply
Take one outcome at 60%. It comes in six times out of ten. Now add a second 60% outcome from another match. Of those six times, the second one also comes in only 60% of the time: 0.6 × 0.6 = 0.36, so 36%. A third leg cuts that again, to 21.6%.
Each new leg keeps only part of what was left. That’s why the combined number falls so quickly, even when every single leg looks reasonable on its own.
| Legs | Every leg 60% | Every leg 80% | Every leg 90% |
|---|---|---|---|
| 1 | 60.0% | 80.0% | 90.0% |
| 2 | 36.0% | 64.0% | 81.0% |
| 3 | 21.6% | 51.2% | 72.9% |
| 4 | 13.0% | 41.0% | 65.6% |
| 5 | 7.8% | 32.8% | 59.0% |
| 6 | 4.7% | 26.2% | 53.1% |
Even “safe” legs add up
Legs at 80% feel close to certain. Five of them together come in only about one time in three (32.8%). Even six legs at 90% each, which sounds very safe, come in only about half the time (53.1%).
Turn it around: with three 60% legs, at least one leg fails about 78% of the time (100% − 21.6%). A failed combo is the normal case, not bad luck.
Real combos rarely have equal legs
In practice the legs differ. A 70%, a 60% and a 55% leg give 0.70 × 0.60 × 0.55 ≈ 23.1%. The rule doesn’t change: multiply every leg.
When multiplying is wrong: legs from the same match
Multiplying works when the legs don’t influence each other, and outcomes from different matches are close to that. Two outcomes from the same match are not: if one team dominates, that also changes how many goals are likely. Multiplying linked outcomes gives a number that looks precise but isn’t.
That’s why Edgity’s Combo Lab never takes more than one leg from the same match.
How Combo Lab shows it
In the Edgity app, Combo Lab works with today’s matches. You choose an odds band and pick matches from the list. For each match it uses the model’s outcome in that band, multiplies the legs, and shows the combined chance straight away, before you decide anything.
The point isn’t to make a combo look better. It’s to show its real chance.
The takeaway
Before trusting a combo, multiply. If the result surprises you, the combo was always that hard; the single legs just made it look easier.