No quiero hacerle daño a nadie.

Could someone please explain the need for the le?

The “le” is used because of the “a” in front of the object, which is necessary because it refers to a person. In general, whenever a person is a direct object of a verb in Spanish it is treated as an indirect object, with the preposition “a” in front of the word itself, and then using “le” instead of “lo” or “la”.

I’m not 100% sure if it’s necessary in this case though, to me it sounds more natural though to have it and I think it would sound strange without it, but I’m not a native speaker. Perhaps a native speaker could explain or verify whether this would be wrong to omit it.

I’ll give this a try. I expect I’ll be corrected, but what the heck… nada aventuró nada ganado.

So, “I don’t want to hurt anyone” is the translation.

My first answer is that the “le” is an example of a redundant object pronoun. The “a nadie” is sufficient, but native Spanish speakers like to add a “le” because, well, because they do.

My second answer is based on the fact that “hacer daño” is a transitive verbal phrase. Moreover, the “le”, being a indirect object pronoun, indicates to me that in Spanish “to hurt someone” with this phrase is not actually like “to help someone”, which uses a direct object pronoun (“lo ayudo”). So what’s different?

The word “daño” is a noun indicating damage or harm. Perhaps with hacer, the “correct” translation is “to make or do damage” or “to make or do harm”. In this way, the “daño” now takes on the role of a direct object. Together with “nadie” as the obvious indirect object, as in “hacer algo a alguien”, I think it is possible to explain all the pieces.

I think this is correct, but I’ll hit that Reply button with fingers crossed.