With every new species discovered, it unlocks new pieces of the biological puzzle. It increases our knowledge of that Genus, Class or Order and that information that we discovered from the new species can also be used in different applications. There are many more reasons but these are just a few.
Um I think that scientists should keep looking cuz like 2 days ago I saw a bug that nobody's ever seen before it was like red and stuff but we should find more of them and more of other aminals cuz we might need to know what they eat and stuff for like a trivia game or something so I think that they should keep looking
We have only just recently discovered a new sub-species of humans: the Denisovans. We have also fairly recently found that all modern humans, primarily those tested in Asia and Europe, 2.5% neanderthal, on average, and that all humans outside of sub-saharan Aftica have neanderthal DNA.
These are quite significant findings, and those are within sub-groups in our own species.
New terrestial species may hold unfathomable secrets about the past of ourselves or our earth. They may assist in aleviating the ails of kur present world, and even hold the key to our future survival, well being, and prosperity.
Knowing our fellow earthlings is just an extension of knowing our home and ourselves that much better.