Science is a collaborative effort. No one person can do it all by themself. That single person can try, but it's more effective to work together with many teams of people. This is why standards are needed so everyone is on the same page. Sometimes this doesn't always happen such as when someone uses feet vs someone using meters. Yes there are ways to convert back and forth, but it's easier to stick to one system. It avoids potential confusion.
One famous example of this is a mars rover that overshot its target because scientists forgot to convert to meters. Unfortunately the rover crashed and the project had to be scrapped.