>>12574901>If scientists have the technology to make a vaccine in 1 yearWe didn't have the technology until recently. Most of the vaccines ready now used techniques only developed within the last 10 years, and only made practical on a mass scale even more recently. Others used ideas that showed promise, but would be expensive to test, and therefore impractical when already working but slower methods were available. Be aware that for every one of the vaccines now approved, dozens failed at some stage of the development process or are still in development.
>why do they spend 5-10 years instead of 1 year?Fast, good, cheap: choose two. Vaccine development has historically prioritized the latter two. Covid vaccine development got the first two. There are also a lot of things usually done sequentially that got done in parallel, one of the biggest being the preparation of millions of doses before effectiveness was verified.
Also, coronavirus in general was a known quantity: MERS and SARS had already gotten a ton of research, and potential vaccination methods identified, which meant that vaccine development was able to proceed much more quickly following the already existing proposals.
