Whenever we do something we expect some results. Usually these results conform to some goal. When you are on a path which leads to nowhere, it means that if you continue doing what you are doing, or you continue in the same direction, then you can't possibly achieve any goals that you may have had in mind.

"leads nowhere" = achieves nothing You can also say "road to nowhere" (like the famous Talking Heads song) or "path to nowhere" or "going nowhere". Imagine it like a real journey, where you are aiming towards something, but arrive at nothing. "(1) The way the company deals with industrial waste leads nowhere. It exacerbates environmental problems. " I corrected the English (exacerbate = to make a bad thing worse) "(2) The negotiation is leading nowhere and reaches no conclusion." Great example. You could also say "The negotiation is going nowhere..." which sounds more common/natural to me, but your sentence is not wrong. More examples (adapted from the internet): "Trying to talk sense into Joe leads nowhere. He has already made up his mind." "Getting to know Chad by reading its Constitution leads nowhere: the reality is quite different." "over-intensive farming leads nowhere except to mad cows" "Despite Government promises, the assistance plan does not meet the needs of the people, and leads nowhere." "Violence leads nowhere" In all these cases you could replace "leads nowhere" with "achieves nothing"