For the confident travel in Nepal, travel insurance is needed. It is not mandatory if you are in Nepal for the tours and lower altitude treks. If you are going to moderate or alpine treks, insurance is essential. If any kinds of accidents or any types of health problems arise and if you have insurance, you will get a quick helicopter rescue from the mountains. Because, there will not be good hospitals in the mountain region. It is same in peak climbing and mountaineering.
Travel insurance should be done in your own country. Insurance in Nepal may not cover the high altitude rescue and high medical expenses. Travel confidently with an insurance.