Some travellers choose organised group tours, while others like to plan their own journeys. Both styles have merits, but I personally prefer independent travel for most trips.
People who book group tours value convenience and security. Everything, including flights, hotels, transport and sightseeing, is arranged in advance, so there is little stress, which is especially useful in unfamiliar countries or for people who are short of time. Local guides provide knowledge and explain the history and culture of the places visited, and travelling in a group is considered safer, particularly for elderly people or those who do not speak the language. Tours can also be a good way to meet other travellers.
By contrast, independent travellers enjoy freedom and flexibility. They can stay longer in places they like, skip those they do not and change plans if the weather is bad or they hear about an interesting event. It is often cheaper, as they can choose hostels, local restaurants and public transport rather than paying for a package that includes profit for the tour operator. Many also feel that independent travel is more authentic. Without a fixed timetable, they are more likely to wander into small neighbourhood cafes, talk to local people and discover things which are not listed in the brochure.
My own view is that independent travel is more rewarding, since it encourages curiosity, problem-solving and personal contact with the places visited. However, this depends on experience and confidence. For a first visit to a remote or complicated destination, a guided tour may be the more sensible choice, and some travellers combine both by booking a tour for part of their trip.
In conclusion, group tours offer ease and safety, while independent travel offers freedom, savings and authenticity, and the best choice depends on the traveller and the destination.