I have no idea where you get these numbers, let alone lead them to this interpretation. According to the most recent research Germany suffered in between 4,4 and 5,3 military casualties, Japan suffered between 2,1 and 2,3 million military casualties, Italy somewhere around 330.000 military casualties (which does not include the Italians fighting against Fascism after September 1943), Bulgaria 18.000 military casualties, Finland (though their case for inclusion in the Axis is debatable) between 84.000 and 92.000 military casualties, Hungary around 300.000 and Romania also around 300.000. While the Ustasha and Vichy France are not included here, that alone puts the Axis military casualties at minimum 7.5 million people.

Using the minimum estimate of 21 mil. military casualties in WWII and subtracting the minimum of the Axis casualties, we reach 13,5 million casualties. Subtracting from that the minimum number of Soviet military casualties, which numbers around 8 million people, we arrive at a minimum number of 5,5 million military casualties for all the Allies except the Soviets and that includes everything from Norway to China with e.g. the US according to the latest US Congressional Report on military death tolls from 2010 numbering 407.316.

And also, let's talk about the Soviet number and why particularly in the case of WWII gauging the effectiveness of a military by their losses (by that metric Iran or Mongolia with 200 or 300 military casualties would be the most effective fighting forces in WWII) is not a good metric: Included in the generally accepted number of 8.6 Soviet military casualties are the number of dead POWs, seeing as they are usually counted as military deaths. But the problem there is that between 3 million and 3,3 million Soviet POWs died from being starved by the Nazis.

The Wehrmacht instated a policy of deliberate starvation of Soviet POWs in 1941 with the argument that they were subhumans and not needed and only served as "useless eaters". Within the time span of Summer 1941 to March 1942 when this policy was officially changed due to the labor shortage in Germany, 1,5 million Russian POWs starved and over the course of the rest of the war, another estimated 1,5 million Russian POWs, which amounts to a whooping 57% of all Russian POWs in German captivity in WWII also died to maltreatment, starvation, concentration camp imprisonment and other causes related to their treatment. So, in essence, without the deliberate policy of murder instituted by the Nazis state (which included the Einsatzgruppen murder of Jewish and East Asian Soviet POWs), the Soviet military casualty count numbers more around 5 million or about equal with the German military.

So, basically, your premise is a bit off here.

Sources:

• Micheal Clodfelter: Warfare and armed conflicts: a statistical reference to casualties and other figures, 1500–2000.

• Rüdiger Overmans: 55 Millionen Opfer des Zweiten Weltkrieges? Zum Stand der Forschung nach mehr als 40 Jahren. In: Militärgeschichtliche Mitteilungen, 48. Jg., Nr. 2/1990, S. 103–121.

• For the Soviet POWs see: Christian Streit: Keine Kameraden: Die Wehrmacht und die sowjetischen Kriegsgefangenen 1941-1945.