Why is it important to disambiguate the words "proof" and "evidence"?

to me, they are equal to each other. What's more important is the add qualifier like "DIRECT vs INDIRECT" in front of proof/evidence. For example, in evolution, no, we can't see an ancestral monkey transforming into man in real-time, so we don't have direct evidence. But we have a lot of indirect evidence such as fossils + DNA to suggest that it is true.