What role did the alliance system play in preventing Austria-Hungary and Serbia from coming to a settlement?

Conflict between Serbia and Austria-Hungary had been happening throughout most of the 19th century and beginnings of the 20th century particularly due to the Austria-Hungary empire's interest in annexing the Balcan region of Bosnia to their territory. However, despite the dispute and the fact that Russia intervened in favor of the Serbians to deflect the attempt of the Austria-Hungary empire, open war did not take place.

The reason why it was not possible for these two nations to settle their dispute, aside from the persistence of the Austrian-Hungarians to take over the Bosnian region, was the constant intervention from the Russian empire who did not wish, for its own interests, to allow the Austrian-Hungarians to take control of a territory that not only was rich in resources they needed but also had many Russian-born inhabitants. The alliance system, which in essence is the agreement between nations to come together whenever the other needs assisstance, especially military-wise, puts forward the interests of the parties involved over the individual needs of each nation and because the Russian empire was the stronger party in the Russian-Serbian alliance, their interests were prioritized over the others'.

When the First World War erupted, after the assassination of Archduke Ferdinand of Austria-Hungary by Serbian terrorists, the alliance system did not just band Russia and Serbia together to confront the attacking Austria-Hungarian empire, but it also forced other nations to join sides and thus one of the greatest world conflicts ensued.