Do travellers need a car in Montenegro?
You do not need a car for every Montenegro trip, but it changes the country. Buses work for the main towns; a car makes mountains, viewpoints, Lake Skadar, Lovćen and smaller coastal stops far easier.
Answer
If your trip is Kotor, Budva, Tivat and a few main towns, public transport, taxis and tours can cover a lot. The moment you want Durmitor, lake viewpoints, flexible beach stops or the road above the bay, a car becomes less of a luxury and more of a route tool. It also brings trade-offs: narrow roads, parking stress, summer traffic and mountain driving. The best answer is not “always rent” or “never rent”. Rent when the route needs freedom. Skip it when the car would spend half the trip parked badly in crowded coastal towns.