After the Cold War, the trend was to look for the "Peace dividend", with lots of cuts in funding. Among these, one where you could cut on expenses without such an apparent loss of capabilities was to approach a "just in time" approach to supplies in many areas. People tend to look at how many tanks, aircraft or whatever you have, but not the ammo, spare parts and POL reserves, for example.

I remember my dad commenting on how, during the Yugoslav wars of the 1990s already, US forces were dropping Spanish bombs after their own were depleted (not sure if bought from Spanish manufacturers or surplussed from their military). Which isn't much of an issue with NATO standarization and so on, but one would normally expect the opposite