All of the vaccines that are being used for COVID are novel. They're being invented for the first time for this purpose. The manufacturers are having to not only develop the vaccines and do the clinical trials, but also scale up the manufacturing of the vaccines. They start slowly and then they build.
All countries are interested in the very first vaccines. The companies are trying to distribute out to multiple countries at the same time. The amounts start out small and then they build over the course of the coming year.