Probably because that's already happened a lot, but there are things we get right, science is an ongoing process, it's why scientists are very reluctant to say things definitively and instead say stuff like "research indicates" or "it's likely that" or so on to that extent. I think this makes science more trustworthy, of course media often skips that and says things like "scientists say chocolate causes cancer" or something when in actuality it'd be more like "mice who were exposed to this chemical that can also be found in small amounts in the cacao plant had higher rates of cancer than a control group that wasn't exposed to the chemical" and this sort of misrepresenting makes science seem less credible. It's why media literacy is important. A lot of what we "know" isn't things we know as fact but things that we have indications of and science acknowledges that, unfortunately popular media often ignores that.