Learn Italian: Non c'è mai nessuno spreco di tempo qui. - There is never any waste of time here.

The adjective nessuno drops its final -o (becoming nessun) before most masculine words. However, because spreco starts with an 's' followed by a consonant (an 'impure s'), it keeps the full nessuno form. This follows the exact same rule that makes us say uno spreco instead of un spreco.

The sentence uses non, mai, and nessuno. Is it normal to have three negative words?

Yes, Italian allows you to stack negative words! When words like mai (never) and nessuno (any/no) appear after the verb, you still must put non before the verb. So, literally saying 'there is not never no waste' is the perfectly grammatically correct way to express 'there is never any waste' in Italian.

Doesn't nessuno usually mean 'nobody'?

It means 'nobody' or 'no one' when used alone as a pronoun. But here, it is acting as an adjective because it is attached directly to the noun spreco (waste). When used as an adjective, nessuno translates to 'no' or 'not any'.

Is spreco di tempo a fixed expression?